Home
Virtual Herbarium
Services
Resources
K-12 Educational Materials
Site Map

Home` > Resources > Glossaries > Botanical Dictionary

Botanical Dictionary

The following list of terms and definitions is from Albert E. Radford, William C. Dickison, Jimmy R. Massey, and C. Ritchie Bell, Vascular Plant Systematics, 1974, Harper & Row Publishers. All rights are reserved.

 

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Abaxial.   Away from the axis; the lower surface of the leaf; dorsal

Abcissent.   Falling off or separating at a specific separation (abcission) layer, as in most deciduous plants

Acarpous.   No carpels or carpellate whorl; no pistil

Accessory Bud. Buds lateral to or above axillary buds; Accessory Organs - The calyx and corolla

Accrescent.   Growing after flowering or bud development has occurred, as the sepals in Hypericum and bud scales in Carya

Accumbent or Pleurorhizal.   Reclinate with cotyledon edges against hypocotyl

Acerose.   Needle-shaped; sharp

Achene.   A one-seeded, dry, indehiscent fruit with seed attached to fruit wall at one point only, derived from a one-loculed superior ovary

Achenecetum.   An aggregation of achenes, as in Ranunculus

Achlamydeous.   Without perianth

Acicular.   Needlelike, round or grooved in cross section

Aciculate .   Finely marked as with pin pricks, fine lines usually randomly arranged

Acrocaulous.   With terminal branches

Acrocidal Capsule.   One that dehisces through terminal slits, or fissures, as in Staphylea

Acrodromous.   With two or more primary or strongly developed secondary veins diverging at or above the base of the blade and running in convergent arches toward the apex over some or all of the blade length, the arches not basally curved

Acropetal.   Developing upward, toward apex

Acroramous.   Leaves terminal, near apex of branch

Acroscopic.   Facing apically

Actinodromous.   With three or more primary veins diverging radially from a single point at or above the base of the blade and running toward the margin, reaching it or not

Actinomorphic or Radial.   With floral parts radiate from center like spokes on wheel

Actinostele.   A protostele having a xylem core in the form of radiating ribs, as viewed in transverse section

Aculeate.   Prickly

Acuminate (Base narrowly cuneate).   Margins straight to convex forming a terminal angle of less than 45

Acute (Base cuneate).   Margins straight to convex forming a terminal angle 45-90

Adaxial.   Next to the axis; facing the stem; ventral

Adherent.  With unlike parts of organs joined, but only superficially and without actual histological continuity

Adnate.   With unlike parts or organs integrally fused to one another with histological continuity

Adventitious.   Arising from organ other than root; usually lateral

Aerating or Knee.   Vertical or horizontal aboveground roots

Aerial or Epigeous.   Above the ground or water, in the air; aerial stem - an erect stem arising from a horizontal rhizome

Aerocaulous.   With aerial stems

Aerophyllous.   With aerial leaves

Aestival.   Appearing in summer

Agamandrous.   Inflorescence with neuter flowers inside or above and staminate outside or below (agamandrocephalous)

Agamogynous.   Inflorescence with neuter flowers inside or above and pistillate outside or below (agamogynecephalous)

Agamohermaphroditic.   Inflorescence with neuter flowers inside or above and hermaphroditic outside or below (agamohermaphrodicephalous)

Agamous or Neuter.   Without sex; sexual organs abortive

Agglomerate, Conglomerate, Crowded, or Aggregate.   Dense structures with varied angles of divergence

Aianthous or Semperflorous.   With flowers appearing throughout the year

Alate.   Winged

Allagostemonous.   Having stamens attached to petal and torus alternately

Allautogamy.   Cross- and self-fertilization in same plant, as in Viola

Allogamy or Xenogamy.   Cross-fertilization in plants

Allopatric.   Isolated, separated

Alternate.   One leaf or other structure per node

Alveolate.   Honey-combed

Ament or Catkin.   A unisexual spike or elongate axis with simple dichasia that falls as a unit after flowering or fruiting

Amorphic or Paleomorphic.   Flowers without symmetry; usually with an indefinite number of stamens and carpels, and usually subtended by bracts or discolored upper leaves; e.g., Salix discolor, Echinops ritro (mostly fossil forms)

Amphicarpous.   With fruits in two environments; e.g., aerial and subterranean

Amphiflorous.   Flowers above and below ground, as in Amphicarpum

Amphisarca.   A berry-like succulent fruit with a crustaceous or woody rind, as in Lagenaria

Amphitropous.   With body bent or curved on both sides so that the micropyle is near the medially attached funiculus

Amplexicaul.   Completely clasping the stem

Ampliate.   Enlarged; dilated

Anadromous.   Having the first lobe or segment of a pinna arising basiscopically in compound leaves

Anatropous.   With body completely inverted so that funiculus is attached basally near adjoining micropyle area

Ancipital.   Two-edged

Andragamous.   Inflorescence with staminate flowers inside or above and neuter flowers outside or below (andragamocephalous)

Androdioecious.   Some plants with staminate flowers and some with perfect flowers

Androecium.   One or more whorls or groups of stamens; all stamens in flower

Androgynecandrous.   Inflorescence with staminate flowers above and below pistillate, as in the spikes of some species of Carex

Androgynophore.   The stipe or column on which stamens and carpels are borne

Androgynous.   Inflorescence with staminate flowers inside or above and pistillate outside or below (androgynecephalous)

Androhermaphroditic.   Inflorescence with staminate flowers inside or above and hermaphroditic outside or below (androhermaphrodicephalous)

Andromonoecious.   Plant with staminate and perfect flowers

Anemophily.   Pollinated by wind

Angustate.   Narrow

Anisocarpous.   With unequal carpels

Anisocotylous.   With unequal cotyledons

Anisolateral.   With unequal sides

Anisopetalous.   With unequal petals

Anisophyllous.   With unequal leaves

Anisostylous.   With unequal styles

Annotinal or Yearly.   Appearing yearly

Annual.   Living one year or less. Winter Annual - Living less than one year but through the winter; germination usually in late fall, and usually flowering and fruiting in early spring

Annular.   Ring-like

Annulus.   Thick-walled ring of cells on the sporangium

Anomalicidal or Rupturing Capsule.   One that dehisces irregularly, as in Ammannia

Anterior.   Anterior Lobes - The lobes away from axis, toward the subtending bract, abaxial lobes; Anterior Ridges, Lines, Grooves - The lines, grooves, ridges in or on the dorsal side, abaxial, within the perianth

Anther.   Pollen-bearing portion of stamen

Antheridium.   The male sex organ producing the sperm

Anthesis.   Time of flowering; opening of flower with parts available for pollination

Anthocarpous.   Having a body of combined floral and fruit parts, as in multiple fruits

Anthotaxis.   Arrangement of sporophylls, primarily reproductive in function

Anthropophily.   Pollinated by man

Antipetalous.   Opposite the petals

Antisepalous.   Opposite the sepals

Antitropous.   With radicle pointing away from hilum

Antrorse.   Bent or directed upward

Apetalous.   No petals or corolla

Aphyllopodic.   Without blade-bearing leaves at base of plant

Aphyllous.   Without leaves, no whorls of leaves

Apical or Terminal.   At the top, tip, or end of a structure

Apiculate.   More than 3:1 l/w, usually slightly curled and flexuous

Apocarpous.   With carpels separate

Apogamy.   Producing sporophytes from a gametophyte without fertilization

Apopetalous or Choripetalous.   With separate petals

Apophysis.   Exposed outer surface of either an ovuliferous scale or megasporophyll as seen when the cone is closed

Aposepalous or Chorisepalous.   With separate sepals

Apospory.   Producing gametophytes directly from a sporophyte without producing spores

Apostemonous.   With separate stamens

Appendicular.   Typical stamen with a variously-shaped or modified, protruding connective, as in Viola

Applanate or Plane.   Flat, without vertical curves or bends

Appressed or Adpressed.   Pressed closely to axis upward with angle of divergence 15° or less

Arachnoid.   Cobwebby

Arborescent.   Tree-like in appearance and size

Archegonium.   The female sex organ producing the egg

Arcuate.   Curved like a crescent, can be downward or upward

Areolate.   Divided into many angular or squarish spaces

Areoles.   The spaces formed by a vein network

Arhizous.   Without roots, no whorls of roots

Aril.   Outgrowth of funiculus, raphe, or integuments; or fleshy integuments or seed coat, a sarcotesta at base of the fleshy seed; e.g., Cepalotaxus

Arillate.   General term for an outgrowth from the funiculus, seed coat or chalaza; or a fleshy seed coat

Aristate.   More than 3:1 l/w, usually prolonged, straight and stiff

Articulate.   Generally meaning having a joint as in leaves, leaflets or stems, as in heterophyllous species of Selaginella; or having a swollen area, often discolored, at the point of branching of the stem

Ascending.   Directed upward with an angle of divergence of 16-45°

Asepalous.   No sepals or calyx

Asperous.   Having a rough surface

Assurgent.   Directed upward or forward

Astemonous or Anandrous.   No stamens or androecium

Astylocarpellous.   Without a style and a stipe

Astylocarpepodic.   Without a style, with a stipe

Astylous.   Style absent

Asymmetric.   Without regularity in any dimension

Attenuate.   Elongate, tapering, usually applied to base

Auriculate.   Lobe rounded; sinus depth variable; outer margin concave, inner convex or straight

Auriculiform.   Usually obovate with two small rounded, basal lobes

Autogamy.   Self-fertilization in a single flower

Autumnal.   Appearing in autumn

Awl-shaped Leaf.   Subulate; narrow, flat, stiff, sharp-pointed, usually less than 1/2 in. long; e.g., Juniperus

Axial.   With branches arising from buds in leaf axil

Axile.   With the placentae along the central axis in a compound ovary with septa

Axillary or Lateral.   In axils of leaves or leaf scars; axillary leaves - leaves borne in the axils of branches, as in heterosporous species of Selaginella Baccacetum or Etaerio.   An aggregation of berries, as in Actaea

Baccate.   Juicy and very succulent

Balausta.   Many-seeded, many- loculed indehiscent fruit with a tough, leathery pericarp, as in Punica

Banded.   Transverse stripes of one color crossing another

Barbed.   With short, rigid reflexed bristles or processes

Barbellate.   Minutely barbed

Bark.   Tissues of plant outside wood or xylem

Basal or Radical.   At the bottom or base of a structure

Base.   bottom or lower portion

Basicaulous.   With basal branches

Basicaulous.   Near base of stem

Basicidal Capsule.   One that dehisces through basal slits or fissures, as in some species of Aristolochia

Basifixed.   Anther attached at its base to apex of filament

Basipetal.   Developing downward, toward base

Basipetiolar.   At the base of the petiole

Basiramous.   Leaves on lower part of branch

Basiscopic.   Facing basally

Bast bundles (peripheral strands).   bundles of thick-walled cells parallel to the midrib, as in Isoetes

beard.   A tuft, line or zone of trichomes

Bearded or Barbate.   With long trichomes usually in a tuft, line or zone

Bent.   Foliate embryo with expanded and usually thick cotyledons in an axile position bent upon the hypocotyl in a jacknife position

Berry.   Fleshy fruit, with succulent pericarp, as in Vitis

Bibacca.   A fused double berry, as in Lonicera

Bicarpellate.   Two-carpelled

Bicrenate or Doubly-crenate.   With smaller rounded teeth on larger rounded teeth

Bidentate.   Two-toothed

Biduous.   Lasting two days

Biennial.   Living two years, usually flowering second year

Biferous.   Appearing twice yearly

Bifid.   Cut or divided into two lobes or parts

Biflorous.   Flowering in autumn as well as in spring

Bifoliolate, Geminate, or Jugate.   With two leaflets from a common point

Bifurcate.   Divided into two forks or branches

Bigeminate, Bijugate.   With two orders of leaflets, each bifoliolate; doubly paired

Bilabiate.   Two-lipped, with two unequal divisions

Bilocular.   Two-locular

Bimestrial.   Periodicity: occurring every two months; duration: lasting two months

Binate.   Twinned

Bipalmate.   Twice palmate

Bipinnate.   Twice pinnate

Biseriate.   Two-rowed; in two series

Biserrate or Doubly-serrate.   With sharply cut teeth on the margins of larger sharply cut teeth

Bisexual.   Both sexes in same flower (monoclinous, perfect)

Biternate.   With two orders of leaflets, each ternately compound

Blade.   The expanded portion of a leaf

Blastocarpous.   Germination of seeds while within the pericarp, as in Rhizophora

Blotched.   The color disposed in broad, irregular blotches

Bordered.   One color is surrounded by an edging of another

Botuliform.   Sausage-shaped

Bract.   Modified, usually reduced, leaf in the inflorescence

Bracteal and Laminar.   May be localized or found over entire structure

Bracteole or Bractlet.   A secondary or smaller bract

Bristle.   A stiff, strong trichome, as in the perianth of some members of the Cyperaceae

Bristly.   Beset with bristles

Brochidodromous.   With a single primary vein, the secondary veins not terminating at the margin but joined together in a series of prominent upward arches or marginal loops on each side of the primary vein

Bud.   Immature vegetative or floral shoot or both, often covered by scales. Bud Primordium - Meristematic tissue that gives rise to a lateral bud

Bulb.   A short, erect, underground stem surrounded by fleshy leaves

Bulbel.   A small bulb produced from the base of a larger bulb

Bulbil.   A small bulb or bulb-like body produced on above ground parts

Bulblet.   A small bulb, irrespective of origin; a small, bud-like vegetative propagule produced on the leaves of some ferns

Bullate.   Puckered or blistered

Bur (Involucre).   Cypsela enclosed in dry involucre, as in Xanthium

Buttress.   Roots with board-like or plank-like growth on upper side, presumably a supporting structure

Caducous.   Dropping off very early, usually applied to floral parts

Calcarate.   Spurred

Calceolate.   Slipper-shaped, as in the corolla of Cypripedium

Callosity.   A thickened, raised area, which is usually hard; a callus

Calybium.   A hard one-loculed dry fruit derived from an inferior ovary, as in Quercus

Calyx.   The lowermost whorl of modified leaves, sepals

Campanulate.   Bell-shaped; with flaring tube about as broad as long and a flaring limb

Campylodromous.   With several primary veins or their branches diverging at or close to a single point and running in strongly developed, basally recurved arches which converge toward the apex, reaching it or not

Campylotropous.   With body bent or curved on one side so that micropyle is near medially attached funiculus

Canaliculate.   Longitudinally grooved, usually in relation to petioles or midribs

Cancellate or Clathrate.   Latticed

Canescent or Incanous.   Covered with dense, fine grayish-white trichomes

Cantharophily.   Pollinated by beetles

Capillate.   Hair-shapedCapitate.   Head-like Capitulum or Head.   A determinate or indeterminate crowded group of sessile or subsessile flowers on a compound receptacle or torus

Carina.   Keel. Carinal Canal - A canal beneath a stem ridge associated with a vascular bundle

Carinate.   Keeled

Carnose or Sarcous.   Fleshy

Carpel.   The female sporophyll within flower; floral organ that bears ovules in angiosperms; unit of compound pistil

Carpophore.   Floral axis extension between adjacent carpels, as in the Apiaceae

Carpopodium.   Short, thick, pistillate stalk

Carpotaxis.   Arrangement of fruits, reproductive in function

Cartilaginous.   Hard and tough but flexible

Carunculate.   With an excrescent outgrowth from integuments near the hilum, as in Euphorbia; fibrous with stringy or cord-like seed coat, as mace in Myristica

Caryopsis or Grain.   A one-seeded dry, indehiscent fruit with the seed coat adnate to the fruit wall, derived from a one-loculed superior ovary

Catadromous.   Having the first lobe or segment of a pinna arising acroscopically in compound leaves

Cataphyll.   Rudimentary scale leaf produced by seedling, usually in cryptocotylar species

Caudate (Base attenuate).   Acuminate with concave margins

Caudex.   A short, thick, vertical or branched perennial stem usually subterranean, or at ground level

Cauline.   May be all over (general) or along the ribs (costal), or in the grooves (canaliculate)

Caulocarpic.   Plants having the stem living for many years, bearing flowers and fruits

Caulous.   With branches more or less evenly spaced along trunk

Central Canal.   The large centrally located air space in the stem

Centrifugal.   Developing from the inside outward, or from top downward

Centripetal.   Developing from the outside inward, or from bottom upward

Centroramous.   At the center of the branch

Ceraceous.   Waxy

Cernuous.   Drooping

Cespitose.   Short, much-branched, plant forming a cushion

Chaff or Pale.   Scale or bract at base of tubular flower in composites

Chalaza.   End of ovule opposite micropyle

Chalazogamy.   Pollen tube entrance through chalaza

Channelled or Canaliculate.   With a longitudinal groove

Chartaceous.   Papery, opaque and thin

Chasmantheric Pollination.   Pollen transferred from a normally dehisced anther by a pollinating agent with pollen grain germination on the stigma and subsequent growth of the pollen tube through stigma, style and the ovule into the embryo sac

Cheiropterophily.   Pollinated by bats

Chlamydeous.   With perianth

Ciliate.   With conspicuous marginal trichomes

Ciliolate.   With tiny or small marginal trichomes

Cincinnus.   A tight, modified helicoid cyme in which pedicels are short on the developed side

Circinate.   With lamina rolled from apex to base with apex in center of coil

Circumalate.   Winged circumferentially

Circumferential.   At or near the circumference; surrounding a rounded structure

Circumscissle Capsule or Pyxis.   One that dehisces circumferentially, as in Plantago

Cirrhous.   More than 10:1 l/w, coiled and flexuous

Cladode (phylloclad).   A flattened main stem resembling a leaf

Cladodromous.   With a single primary vein, the secondary veins not terminating at the margin and freely ramified toward it

Cladoptosic.   Shedding of branches, stems and leaves simultaneously, as in Taxodium

Clambering.   Sprawling across objects, without climbing structures

Clasping.   Partly surrounding the stem.

Clavate.   Club-shaped

Claw.   The long, narrow petiole-like base of a sepal or petal

Cleft.   Indentations or incisions cut 1/4-1/2 distance to midrib or midvein

Cleistantheric Pollination.   Pollen not transferred from a normally dehisced anther by a pollinating agent; pollen grain germinates within the anther with subsequent growth of the pollen tube through the anther wall and ovary wall into the ovule and embryo sac

Climbing.   Growing upward by means of tendrils, petioles, or adventitious roots

Clinanthium.   The compound receptacle of the composite head

Clouded.   Colors are unequally blended together

Clustered, Conglomerate, Agglomerate, Crowded, Aggregate.  Parts dense, usually irregularly overlapping each other

Coalescent.   With like or unlike parts or organs incompletely separated; partially fused in a more or less irregular fashion

Cochleate.   Snail-shaped

Coenocarpium (Various Structures).   Multiple fruit derived from ovaries, floral parts, and receptacles of many coalesced flowers, as in Ananas

Coetaneous.   Flowering as the leaves expand; synantherous

Coherent.   With like parts or organs joined, but only superficially and without actual histological continuity

Coleoptile.   Protective sheath around epicotyl in grasses

Coleorhiza.   Protective sheath around radicle in grasses

Collet.   External demarcation between hypocotyl and root

Columella.   The sterile central part within a mature sporangium or capsule

Column, Gynostemium or Gynandrium.   With fused stamens and carpels (stigma and style) as in Orchis

Columnar.   Erect with a stout main stem or trunk

Comose.   With a tuft of trichomes, usually apical

Complete.   Leaf with blade, petiole, and stipules; flower with four types of floral parts

Compound.   Composed of two or more anatomically or morphologically equivalent units, whether subdivided into them or an aggregate of them

Compressed or Complanate.   Flattened

Conduplicate.   Longitudinally folded upward or downward along the central axis so that ventral and/or dorsal sides face each other

Cone (strobilus).   Aggregation of sporangia-bearing structures at tip of the stem (either sporophylls or scales in the Gymnosperms)

Conical.   Having figure of true cone

Conjugate.   Fused pairs, as the fruits of Lonicera

Connate.   With like parts or organs integrally fused to one another with histological continuity

Connective.   Filament extension between thecae

Connivent.   Convergent apically without fusion

Contiguous.   Touching but not adnate, connate, adherent, or coherent

Continuous.   Symmetry of arrangement even, not broken

Contorted.   Twisted around a central axis; twisted

Contortuplicate.   With weirdly folded corrugate cotyledons

Contractile or Pull.   Roots capable of shortening, usually drawing the plant or plant part deeper into the soil, usually with a wrinkled surface

Convolute.   With one lamina enrolled in another lamina

Cordate (Apex obcordate).   Lobe rounded; sinus depth 1/8-1/4 distance to midpoint of blade; margins convex and/or straight

Cordiform.   Heart-shaped

Coriaceous.   Thick and leathery

Corm.   The enlarged, solid, fleshy base of a stem with scales; an upright underground storage stem

Cormel.   Small corm produced at base of parent corm

Corneous.   Horny

Corniculate.   Horned

Corolla.   The whorl of petals located above the sepals

Corona.   A crown; any outgrowth between the stamens and corolla which may be petaline or staminal in origin

Coronate.   Tubular or flaring perianth or staminal outgrowth; petaloid appendage

Coroniform.   Crown-shaped

Corrugate.   With lamina irregularly folded in all directions, wrinkled

Corymb.   A flat-topped or convex indeterminate cluster of flowers. Compound Corymb - A branched corymb

Costa.   The midvein of a minor divsion of a fern leaf

Costate.   Coarsely ribbed

Cotyledon.   Embryonic leaf or leaves in seed

Cotylespermous.   With food reserve in cotyledon, derived from zygote

Cotyliform.   Cup-shaped

Craspedodromous.   Simple - With a single primary vein, all of the secondary veins and their branches terminating at the margin. Mixed - With a single primary vein, some of the secondary veins terminating at the margin and an approximately equal number otherwise

Crateriform.   Shallow cup-shaped as the involucre of some species of Quercus

Crenate.   Shallowly ascending round-toothed, or teeth obtuse; teeth cut less than 1/8 way to midrib or midvein

Crenulate.   Diminutive of crenate, teeth cut to 1/16 distance to midrib or midvein

Crested or Cristate.   With a terminal ridge or tuft

Crispate.   Curled; margins divided and twisted in more than one plane

Crozier.   The coiled developing leaf of a fern

Cruciform or Cruciate.   Cross-shaped

Crustaceous.   Hard, thin, and brittle

Cryptantherous.   With stamens included

Cryptocotylar or Hypogeous.   With the cotyledons remaining inside the seed; seed usually remaining below ground

Cucullate.   Hooded

Culm.   Flowering and fruiting stems of grasses and sedges

Cupule.   Fused involucral bracts subtending flower, as in Quercus

Curvative or arcuate.   With lamina folded transversely into an arc

Cuspidate.   Acute but coriaceous and stiff

Cyathium.   A pseudanthium subtended by an involucre, frequently with petaloid glands, as in Euphorbia

Cylindric.   Long-tubular

Cymbiform.   Boat-shaped

Cyme or Dichasium.  A determinate, dichotomous inflorescence with the pedicels of equal length. Scorpioid Cyme or Rhipidium - A zigzag determinate inflorescence with branches developed on opposite sides of the rachis alternately. Compound

Cyme - A branched cyme

Cymule.   A simple, small dichasium

Cypsela.   An achene derived from a one-loculed, inferior ovary

Deciduous.   Persistent for one growing season

Declinate.   Directed or curved downward

Decompound.   A general term for leaflets in two or more orders - bi-, tri-etc - pinnately, palmately, or ternately compound

Decumbent.   Reclining or lying on the ground with the tips ascending

Decurrent.   Elongate, extending downward

Decussate.   Opposite leaves at right angle to preceding pair

Deflexed.   Bent abruptly downward

Dehiscent.   Opening regularly by valves, slits, etc., as a capsule or anther

Deliquescent.   Softening and wasting away

Dentate.   Margins with rounded or sharp, coarse teeth that point outwards at right angles to midrib or midvein, cut 1/16 to 1/8 distance to midrib or midvein

Denticidal Capsule.   One that dehisces apically, leaving a ring of teeth, as in Cerastium

Denticulate.   Diminutive of dentate, cut to 1/16 distance to midrib or midvein

Depauperate.   Small and usually poorly developed

Depressed.   Pressed closely to axis downward with angle of divergence of 166-180°

Descending.   Directed downward with an angle of divergence of 136-165°

Determinate.   Growth of plant parts, the size of which is limited by cessation of meristematic activity during the year

Dextrorse.   Rising helically from right to left, a characteristic of twining stems

Diadelphous.   With two groups of stamens connate by their filaments

Diandrous.   With two stamens per flower

Diaphanous.   Translucent

Dichasium.   Cymose inflorescence in which each axis produces a pair of lateral axes

Dichlamydeous.   With perianth composed of distinct calyx and corolla

Dichogamous.   With maturation of stamens or anther and carpels or stigma at different times

Dichotomous.   With branches forking into two more or less equal parts

Diclesium (Calyx).   Achene or nut surrounded by a persistent calyx, as in Mirabalis

Diclinous.   Plant with imperfect flowers; stamens and carpels in separate flowers either monoecious or dioecious

Dicotyledonous.   With two cotyledons

Dictyostele.   A dissected solenostele with each individual bundle a meristele

Dicyclic.   Two-whorled

Didymous.   With stamens in two equal pairs

Didynamous.   With stamens in two unequal pairs

Diffuse.   Spread over a wide surface

Digestive Glands.   Enzyme-secreting glands found mostly on leaves of carnivorous and insectivorous plants

Dilated.   Widened; expanded

Dimerous.   Whorl with two members

Dimidiate.   Divided into unequal halves

Dimorphic.   Having two different sizes and/or shapes within the same species

Dioecious.   Plant with all flowers imperfect, but staminate and pistillate on separate plants

Diplecolobal.   With incumbent cotyledons folded two or more times

Diplostemonous.   With stamens in two whorls, outer opposite the sepals, inner opposite petals

Diplotegium.   A pyxis derived from an inferior ovary

Dipterous.   Two-winged

Disc.   A discoid structure developed from receptacle at base of ovary or from stamens around the ovary

Discoid.   Orbicular with convex faces

Discoidal.   A single large spot of color in the center of another

Discontinuous.   Basal and lateral, basal and terminal, or lateral and terminal; not continuous

Dissected.   Irregularly cut into numerous segments

Distal.   Away from the point of origin or attachment

Distichous.   Leaves 2-ranked, in one plane

Distinct.   With like parts or organs unjoined and separate from one another

Diurnal.   Opening during the day

Divergent, Patent, or Divaricate.   More or less horizontally spreading with angle of divergence of 15° or less up or down from the horizontal

Divided.   Cut 3/4 to almost entire distance to middle of structure

Dolabriform.   Axe-shaped

Dorsal.   Pertaining to the surface most distant from the axis; back of an outer face of organ; lower side of leaf; abaxial. Dorsal Side - Back or abaxial side, or the lower side of a perianth part

Dorsifixed.   Anther attached dorsally and medially to apex of filament

Dorsilaminar.   On dorsal side of blade

Dorsiventral.   Planate and having distinct dorsal and ventral surfaces, the two usually different

Dotted.   The color disposed in very small round spots

Downy.   Covered with short, weak, soft trichomes

Drupe.   A fleshy fruit with a stony endocarp, as in Prunus

Drupecetum.   An aggregation of drupelets, as in Rubus

Drupelet.   A small drupe, as in Rubus

Dwarf.   Very small. Dwarf Shoots or Spurs - Shoots that develop from preformed buds which have very short internodal lengths or intervals

Dyad.   Pollen grains occurring in clusters of two

Eccentric.   Off-center style

Echinate.   Covered with spines

Ectocarp or Exocarp.   Outermost layer of pericarp

Edged.   One color is surrounded by a very narrow rim of another

Elaminate.   Without blade

Elater.   One of four elongate appendages on the spores, as in Equisetum

Elliptic.   With widest axis at midpoint of structure and with margins symmetrically curved

Emarginate.   Lobe rounded; sinus depth 1/16-1/8 distance to midpoint of blade; margins straight or convex

Embryo.   Young sporophyte consisting of epicotyl, hypocotyl, radicle, and one or more cotyledons. Embryo Sac - Female gametophyte. Linear Embryo - Axial embryo several times longer than broad, straight, curved or coiled; cotyledons not expanded; endosperm present or absent

Emergent.   With part(s) of plant aerial and part(s) submersed; rising out of the water above the surface

Emersifolious.   With emergent leaves

Endocarp.   Innermost differentiated layer of pericarp

Endosperm.   Food reserve tissue in seed derived from fertilized polar nuclei; or food reserve derived from megametophyte in gymnosperms

Endospermous or Albuminous.   With food reserve in endosperm or albumen, derived from fertilized polar nuclei

Entire.   Without indentations or incisions on maigins; smooth

Entomophily.   Pollinated by insects

Eophyll.   Term applied to first few leaves with green, expanded lamina developed by seedlings; transitional type leaves developed before formation of adult leaves

Epetiolate.   Without petiole, leaf sessile

Epetiolulate.   Without petiolule, leaflet sessile

Ephemeral.   Germinating, growing, flowering and fruiting in a short period, as most desert herbs

Epicalyx.   Group of leaves resembling sepals below the true calyx

Epicalyx or Calycle.   A whorl of bracts below but resembling a true calyx

Epicormic Shoots or Water Sprouts.   Shoots that develop from dormant lateral buds on the trunk which have very long and frequently variable internodal lengths or intervals

Epicotyl.   Apical end of embryo axis that gives rise to shoot system

Epigyny.   The condition in which the sepals, petals, stamens are attached to the floral tube above the ovary with the ovary adnate to the tube or hypanthium

Epihyperigyny.   The condition in which the sepals, petals, stamens are attached to the floral tube or hypanthium surrounding the ovary; a combination perigyny and partly inferior ovary

Epihypogyny.   The condition in which the sepals, petals, stamens are attached about half-way from the base of the ovary to the partly adnate hypanthium tube; half-inferior insertion of parts

Epimatium.   Fleshy covering of the seed and more or less fused with the integument; arising from the chalazal end of the ovule like an additional integument; e.g., Podocarpus

Epiperigyny.   The condition in which the sepals, petals, stamens are attached to the floral or hypanthium cup above the ovary with the lower part of the hypanthium completely adnate to the ovary

Epipetalous.   With stamens attached to or inserted upon petals or corolla

Epipetiolar.   With branches arising from buds on the petiole

Epipetric.   Upon rock

Epiphyllous.   From a phylloclad or peculiar bract, as in Tilia

Epiphytic.   Upon another plant

Epirhizous.   With roots upon another plant

Episepalous.   With stamens attached or inserted upon sepals or calyx

Epitropous .  Dorsal - Ovule pendulous or hanging, micropyle above, raphe dorsal (away from ventral bundle). Ventral - Ovule pendulous or hanging, micropyle above, raphe ventral (toward ventral bundle)

Equilateral.   With halves or sides equal in shape and size

Equinoctial.   Having flowers which expand and close regularly at particular hours of the day

Equitant.   Leaves 2-ranked with overlapping bases, usually sharply folded along midrib

Eramous.   With unbranched stems

Erect.   Upright

Erose.   Irregularly, shallowly toothed and/or lobed margins; appearing gnawed

Essential Organs.   The androecium and gynoecium

Ethereal Oil Producing Glands.   Mostly aromatic compound producing glands found on various parts of the plant, without definitely known functions

Eucamptodromous.   With a single primary vein, the secondary veins curved upward and gradually iminishing distally within the margin and interconnected by a series of cross-veins without forming conspicuous marginal loops

Eusporangiate.   Having the sporangium develop from a great amount of leaf tissue as opposed to only one or a few cells

Eustele.   A dissected siphonostele with phloem only to the outside of the xylem

Evanescent.   Passing away, disappearing early

Evergreen.   Persistent two or more growing seasons

Evident.   Clearly visible macroscopically

Excentric.   One-sided; off-center

Excurrent.   Running out, as the nerve of a leaf projecting beyond the margin

Exospore or Exine.   Outer spore wall layer

Exsserted.   Projecting out of, beyond

Exstipellate.   Without stipels

Exstipulate.   Without stipules

Falcate or Seculate.   Sickle-shaped

False Veins.   Small vein-like areas of thick-walled cells in the leaves of some lower vascular plants

Farinaceous.   Mealy

Fasciated.   Unnaturally and often monstrously connate or adnate, the coalesced parts often unnaturally proliferated in size and/ or number; e.g., inflorescence of Celosia

Fascicle.   Cluster of needles borne on a minute determinate short shoot in the axil of a primary leaf (bract); e.g. Pinus.

Fascicle Sheath - Closely imbricated bud scales at the base of the fascicle of needles; e.g., Pinus

Fascicled.   Fleshy or tuberous roots in a cluster

Fasciculate.   Leaves or other structures in a cluster from a common point

Fastigiate.   Strictly erect and parallel

Faucal Area.   The throat area

Female, Carpellate, or Pistillate.   Plant with pistillate flowers only

Fetid.   Having an unpleasant, rotten odor

Fenestrate.   With windowlike holes through the leaves or other structures

Fibonacci Phyllotaxis.   A fundamental type of leaf arrangement expressed as a fraction in which each succeeding fraction is the sum of the two previous numerators and the sum of the two previous denominators, i.e., 1/2, 1/3, 2/5, 3/8, 5/13, 8/ 21, etc. The numerator represents the number of turns or spirals around a stem before one leaf is directly above another and the denominator represents the number of leaves in the turns or spirals before one is directly above the other. 2/5 phyllotaxy would mean two twists and five leaves before one leaf is directly above the other or an angle of divergence of 144 between succeeding leaves in the stem (2/5 of 360 ).According to Leppik anthotaxis and semataxis do not necessarily follow the same pattern, with anthotaxis in Michelia cited as being in 2/7, 3/7, 3/8, and 4/10 systems of arrangement.

Fibrous.   With fine, threadlike or slender roots or fibers

Filament.   Stamen stalk

Filiferous.  Filamentose or Filiferous With coarse marginal fibers or threads

Filantherous or Typical.   Stamen with distinct anther and filament with or without thecal appendages, as in Rhexia or Vaccinium

Filiform.   Threadlike, usually flexuous

Fimbriate.   Margins fringed

Fimbriolate.   Minutely fimbriate

Fistulose.   Hollow, as without pith

Flabellate.   Fan-shaped branching

Flabelliform.   Fan-shaped

Flaccid.   Lax and weak

Flagellate.   Bearing flagella, whip-like strands or organs

Fleshy.   Succulent roots

Flexuous.   With a series of long or open vertical curves at right angles to the central axis

Floating.   Upon the surface of the water

Floccose.   Covered with dense, appressed trichomes in patches or tufts

Flotophyllous.   With floating leaves

Flower.   Reproductive structure of flowering plants with or without protective envelopes, the calyx and/or corolla; short shoot with sporophylls and with or without sterile protective leaves, the calyx and corolla

Flushing Shoots.   Shoots that develop from mature terminal buds several times during a season. Terminal bud will develop shoot with new terminal bud which will develop more shoots and a terminal bud which will develop etc. --several times in a season with several flushes of growth.

Fly Trap.   Hinged, insectivorous leaf, as in Dionaea

Folded.   Foliate embryo with cotyledons usually thin and extensively expanded and folded in various ways

Follicetum.   An aggregation of follicles, as in Caltha

Follicle.   A dry, dehiscent fruit derived from one carpel that splits along one suture

Fovea.   Pit or depression containing the sporangium in the leaf base of Isoetes 

Foveolate.   Pitted

Free.   Unlike parts or organs unjoined and separate from one another

Free-adnate.   Hypanthium fused with ovary and having a free limb around or above ovary

Free-central.   With the placenta along the central axis in a compound ovary without septa

Fringe.   The modified margin of a petal, sepal, tepal or lip

Frond.   The leaf of a fern

Fruit.   Matured ovary of flowering plants, with or without accessory parts

Fruticose.   Shrubby

Fugacious.   Ephemeral, usually applied to plant parts

Funicular.   With a persistent elongate funiculus attached to seed coat, as in Magnolia

Funiculus.   Stalk by which ovule is attached to placenta

Fusiform.   Spindle-shaped; broadest in middle and tapering to each end

Galeate.   Helmet-shaped, as one sepal in Aconitum

Geitonogamy.   Fertilization of one flower by another on the same plant

Gelatinous.   Jellylike; soft and quivery

Geminate or Binate.   Paired; in pairs

Gemma.   A vegetative reproductive bud borne on the stem, as in Lycopodium; a multicellular reproductive propagule on gametophytes, as in ferns

Geniculate.   Abruptly bent at a node, zigzag

Geoflorous.   With subterranean flower

Geocarpous.   Fruits below ground, as in Amphicarpum

Gibbous.   Inflated on one side near the base

Gigantic.   Very large

Glabrate.   Without trichomes

Glabrescent.   Becoming glabrous

Glabrous.   Smooth; devoid of trichomes

Gland.   A secreting part or appendage

Glandular.   Covered with minute, blackish to translucent glands

Glans (Involucre).   Nut subtended by a cupulate, dry involucre, as in Quercus

Glaucescent.   Sparingly or slightly glaucous

Glaucous.   Covered with a bloom or smooth, waxy coating

Globose.   Round

Glochidiate.   With barbed trichomes, glochids, usually in tufts

Glomerule.   An indeterminate dense cluster of sessile or subsessile flowers

Glume.   Bract, usually occurring in pairs, at the base of the grass spikelet

Glutinous.   Having a shiny, sticky surface

Granular.   Finely mealy, covered with small granules

Greasy or Unctuous.   Slick, oily, slippery to touch

Gynagamous.   Inflorescence with pistillate flowers inside or above and neuter flowers outside or below (gynagamocephalous)

Gynandrial or Gynostemial.   With fused stamens and carpels (stigma and style) as in the Orchidaceae

Gynecandrous.   Inflorescence with pistillate flowers inside or above and staminate outside or below, as in spikes of some species of Carex

Gynehermaphroditic.   Inflorescence with pistillate flowers inside or above and hermaphroditic outside or below (gynehermaphrodicephalous)

Gynobasic.   Attached at base of ovary in central depression

Gynodioecious.   Some plants with perfect flowers and some with pistillate

Gynoecium or Pistil.   The whorl or group of carpels in the center or at the top of the flower; all carpels in a flower

Gynomonoecious.   Plant with pistillate and perfect flowers

Gynophore.   The stipe of a pistil or carpel

Half-inferior.   Other floral organs attached around ovary with hypanthium adnate to lower half of ovary

Half-terete.   Flat on one side, terete on other; semicircular in cross section

Haplomorphic.   Flowers with parts spirally arranged at a simple level in a semispheric or hemispheric form; petals or tepals colored; parts numerous; e.g., Nymphaea, Magnolia

Hastate.   Lobe pointed and oriented outward or divergent in relation to petiole or midrib; sinus depth variable; margins variable

Hastiform.   Triangular with two flaring basal lobes

Haustorial.   Absorbing roots, within host of some parasitic species

Helicoid Cyme or Bostryx.   A determinate inflorescence in which the branches develop on one side only, appearing simple

Hemianatropous or Hemitropous.   With body half-inverted so that funiculus is attached near middle with micropyle terminal and at right angles

Herb.   A usually low, soft, or coarse plant with annual aboveground stems

Herbaceous.   Soft and succulent

Hermaphrodagamous.   Inflorescence with hermaphroditic flowers inside or above and neuter outside or below (hermaphrodagamocephalous)

Hermaphrodandrous.   Inflorescence with hermaphroditic flowers inside or above and staminate outside or below (hermaphrodandrocephalous)

Hermaphroditic or Monoclinous.   Plant with all flowers perfect

Hesperidium.   A thick-skinned septate berry with the bulk of the fruit derived from glandular hairs, as in Citrus

Heterandrous.   With stamens of different sizes and/or shapes

Heteranthous.   Having different states in two different sets of flowers, only one state present in each set

Heteroblasty.   With juvenile foliage distinctly different from adult foliage in size or shape

Heterocarpous.   With carpels of different sizes and/or shapes

Heterocephalous, Heterocymous, Heterospicous.   Heads, cymes, spikes with flowers of different sexual conditions. Note: other inflorescence word stems could be used for appropriate inflorescence type.

Heterocladous.   With stems of different sizes and/or shapes

Heteromerous or Anisomerous.   With different number of members in different whorls

Heteropetalous.   With petals of different sizes and/or shapes

Heterophyllous.   With leaves of different sizes and/or shapes. Heterophyllous Shoots - Shoots that develop from winter buds which do not contain the primordia of all the leaves to develop during the year

Heterophytous.   Having different states in two different sets of plants, only one state present in each set

Heterosepalous.   With sepals of different sizes and/or shapes

Heterosexual.   Inflorescences or flowers within the plant with different sexual conditions

Heterosporous.   Having two kinds of spores, usually differing in sizeHeterostichus.   With unequal rows

Heterostylous.   With styles of different sizes or lengths or shapes within a species

Heterotropous.   Ovule position not fixed in ovary

Hibernal or Hiemal.   Appearing in the winter

Hilum.   Funicular scar on seed coat

Hip or Cynarrhodion (Receptacle and Hypanthium).   An aggregation of achenes surrounded by an urceolate receptacle and hypanthium, as in Rosa

Hippocrepiform.   Horseshoe-shaped

Hirsute.   Covered with long, rather stiff trichomes

Hirsutullous or Hirtellous.   Minutely hirsute

Hispid.   Covered with very long, stiff trichomes

Hispidulous.   Approaching hispid, minutely hispid

Homandrous.   With stamens of same size and shape

Homanthous.   Having more than one state within each individual flower, all flowers the same

Homocarpous.   With carpels of same size and shape

Homocephalous, Homocymous, Homospicous.   Heads, cymes, spikes with flowers sexually uniform

Homochlamydeous.   With perianth composed of similar parts, each part a tepal

Homogamous.   With maturation of stamens or anther and carpels or stigma at same time

Homophytous.   Having more than one state within each individual plant, all plants the same

Homosexual.   Inflorescences or flowers sexually uniform

Homosporous.   Having spores of only one kind

Homostylous.   With styles of same sizes or lengths and shapes

Hood.   A cover-shaped perianth part, usually with a turned down margin

Horn.   A curved, pointed and hollow protuberance from the perianth

Hyaline.   Thin and translucent or transparent

Hydrophily.   Pollinated by water

Hymenopterophily.   Pollinated by bees

Hypanepigyny.   The condition in which the sepals, petals, stamens are attached to the elongate floral tube or hypanthium above the inferior ovary, as in Oenothera

Hypanthium.   The fused or coalesced basal portion of floral parts (sepals, petals, stamens) around the ovary

Hypanthodium.   An inflorescence with flowers on wall of a concave capitulum, as in Ficus

Hyphodromous.   With a single primary vein and all other venation absent, rudimentaryj or concealed within a coriaceous or fleshy blade

Hypocotyl.   Embryonic stem in seed, located below cotyledons

Hypocotylespermous or Macropodial.   With food reserve stored in hypocotyl, derived from zygote

Hypogynium.   Perianth-like structure of bony scales subtending the ovary, as in Scleria and other members of the Cyperaceae

Hypogyny.   The condition in which the sepals, petals, stamens are attached below the ovary

Hypophyllous.   With small leaves, as bracts, scales, cataphylls

Hypotropous.   Dorsal - Ovule erect, micropyle below, raphe dorsal (away from ventral bundle). Ventral - Ovule erect, micropyle below, raphe ventral (toward ventral bundle)

Hysteranthous.   With leaves appearing after flowers

Imbricate.   Having margins overlapping

Imparipinnate.   Pinnate with a conform terminal leaflet. Imparipinnately Compound - Odd-pinnately compound, with a terminal leaflet

Imperfect or Unisexual.   With stamens or carpels absent in the flower

Implicate.   With both lamina margins folded sharply inwa