abaxial: ​ dorsal; on the side that is away from the axis (in nutlets, the side facing outwards); (compare adaxial)

achene: a dry, indehiscent, one-seeded fruit, with seed attached to pericarp at a single point

acuminate: tapering gradually to a point and forming more or less concave sides

acute: tapering to a pointed apex with more or less straight sides

adaxial: ventral; on the side that is towards the axis (in nutlets, the side facing inwards), (compare abaxial)

aggregate: fruit formed from a single flower with carpels several and distinct

alveolate: texture—reticulated, honeycombed; ridges that intersect to form polygonal cells with a regular size and shape similar to a honeycomb

angular: 2D shape—having sides that meet at acute or obtuse angles

annular: 3D shape—forming a ring

anomalicidal: type of capsular dehiscence, opening irregularly

antrorse: (adv. antrorsely) curved or bent toward the apex (as in 'antrorsely barbed')

apex: the point farthest from the point of attachment, or the "tip" of an organ

apical: at or pertaining to the end of the seed or fruit distal from its point of attachment (i.e., base)

appressed: pressed close to or lying flat against something, as in hairs on grass bract

aril: (broad sense) appendicular structure that wholly or partly envelops a seed and is produced from or a modification of the funicle, raphe, or outer integument; usually fleshy or pulpy, sometimes spongy or tufted-capillate, often brightly colored

aristate: having a bristle-like appendage (e.g., awn)

article: section of a fruit separated from other sections by a constricted joint

awn: a narrow, bristle-like organ, as on the glumes or lemmas of grasses

axial: (of embryo) embryo is situated along the longitudinal axis of the seed and may partially or completely fill the seed

axile: on or of the axis

axis: a straight line through the center of a structure around which the parts are usually symmetrically arranged, as in the stem or rachis of an inflorescence


barbed: (of awns or bristles) with short, sharp, hair-like projections

barbellate: finely or minutely barbed; covered with short, hooked bristles or hairs

basal: at or pertaining to the point of attachment; (of embryo) embryo occupies one end of the seed

beak: a usually firm, terminal appendage, sometimes tapered

bent: (of embryo) embryo is bent at an acute, V-shaped angle with the ends close together and generally thick cotyledons

berry: an indehiscent, fleshy fruit with one or a few to many seeds. The flesh may be homogenous throughout, or the outer part may be hard, firm, or leathery; septa are present in some, and the seeds may be arillate or with a fleshy testa

bifid: two-lobed or two-cleft (usually in reference to an apex)

bilocular: (ovary or fruit) having two locules

blistered: covered with irregular raised, hollow granules that give the surface a bubbled appearance

bony: very hard and rather brittle, like bone

bract: a leaf-like or scale-like plant part, located just below a fruit (especially in grasses), flower, flower stalk, or an inflorescence

bristly: having bristles or stiff hair or hair-like structures


C-shaped: 2D-shape—semiannulate, curved into the shape of the letter 'C'

callus: the hard base of grass florets or spikelets, just above the point of disarticulation

calyx: the outer whorl of the perianth; all the sepals of a flower

capitate: head-shaped; abruptly enlarged on one end to a relatively short, terminal portion

capsule: a dry, dehiscent fruit formed by two or more carpels

carpopodium: an elongation of the base of the gynoecium which looks distinct, as in the achenes of some Asteraceae

cartilaginous: texture—firm, dense, tough, somewhat pliable, and resilient, like cartilage

caruncle: a localized outgrowth of the seed coat near the hilum of the seed; it functions as an elaiosome

caryopsis: a small, indehiscent, dry, fruit with a thin wall surrounding and more or less fused to a single seed

caudate: tapering to a long, tail-like appendage

cerebriform: an irregular brain-like appearance, as the kernel of a walnut

chalaza: the region at the base of the ovule where the integuments are inserted

chartaceous: =papery, papyraceous

ciliate: with a marginal fringe of hairs

circular: (of embryo) linear embryo is curved into an "O" shape

circumscissile: (~pyxis); type of capsular dehiscence, opens by a lid (splitting transversely)

clathrate: latticelike in appearance

clavate: 3D shape—club-shaped, with attachment at or near narrow end (compare obclavate)

coiled: (of embryo) linear embryo is very long and bent to form a coil whereby one end of the embryo is on the outside and the other end near the middle of the seed

colliculate: texture—covered with small, round projections

commissure: the face along which two carpels join, as in the Apiaceae

compressed: flattened; in grasses, used to denote compression (not necessarily flattened) either laterally or dorsiventrally

conical: 3D shape—cone-shaped, with the point of attachment at the broad end

connivent: converging but not fused

cordate: 2D shape—heart-shaped, with attachment at or near the broad end (compare obcordate)

coriaceous: texture—leathery

corky: firm, relatively light, discontinuous but strongly cohesive, and resilient

corolla: the inner whorl(s) of the perianth; all the petals of a flower

cotyledon: a primary leaf of the embryo

craspedium: a one-carpellate fruit splitting transversely into one-seeded segments; seed-bearing segments separate from each other and from the persistent sutures (see fruits of Mimosa diplotricha and Mimosa pigra)

crenate: having a margin with low, rounded or scalloped projections

crenulate: finely crenate (scalloped)

crescent-shaped: 2D shape—arcuate or curved, broadest at the middle, and attenuate to acute ends; like a stylized outline of a first-quarter moon

crisped: irregularly curled, wavy or crinkled

crustaceous: texture thin, dry, indurate, and brittle

cuneiform: =wedge-shaped

curved: (of embryo) linear embryo is curved into an arch or horseshoe with the ends far apart

cylindrical: 3D shape—a cylinder, with parallel sides and a circular cross-section; tubular or rod-shaped


D-shaped: 2D shape—has one straight margin and one curved margin, resembling the shape of the letter D

deciduous: falling off; not persistent

dehiscent: (v. dehisce) splitting open at maturity to release contents (of a fruit)

dentate: regularly spaced, teeth oriented more or less perpendicular to the central axis bearing them

denticidal: type of capsular dehiscence, fruit opening by a series of apical teeth

dimorphic: occurring in two forms

dioecious: having separate male and female flowers or cones on different individuals of the same species

discoid: 3D shape—resembling a disc

disseminule: detachable plant part capable of being disseminated and of propagating, commonly a seed or fruit

dorsal: abaxial; the back of an organ; the side away from the axis (compare ventral)

dorsiventral: pertaining to the dorsal and ventral surfaces

drupe: (indehiscent drupe) a fleshy, indehiscent fruit with one more hard pits enclosing seeds; (dehiscent drupe) a fruit with a dry or fibrous to fleshy or leathery outer husk that early to tardily breaks apart (or opens), exposing one or more nutlike pits enclosing the seeds

drupelet: one drupe of a fruit with multiple drupes, as in blackberries

dry: texture, free or relatively free from water or liquid

dull: reflecting only a low proportion of incident light, with no apparent sheen


elaiosome: a lipid and protein-rich fleshy structure attached to some seeds and fruits, it attracts ants which then disperse the disseminule (e.g., caruncle in the Euphorbiaceae, the aril (outgrowth of the funiculus) in the Fabaceae)

ellipsoid: 3D shape—elliptic

elliptic: 2D shape—oval, oblong-like with the 2 ends narrowing and more or less alike

emarginate: with a shallow notch at apex

endocarp: the inner layer of the pericarp, if divided into layers

endosperm: nutritive starch- and oil-containing tissue present in many seeds

epicarp: outer layer of fruit wall or pericarp, if divided into layers; note here used synonymously with exocarp

exocarp: outer layer of fruit wall or pericarp, if divided into layers; note here used synonymously with epicarp


falcate: shaped like a scythe or sickle

fascicle: a highly reduced branch of a spicate grass panicle consisting of 1–3 whorls of free or fused bristles disarticulating with the spikelets at maturity

fertile floret: a grass floret capable of producing fruit; the fertile floret may possess both male and female, or just female, reproductive structures

fibrous: texture—long, flexible threads, thicker than hairs, that densely cover and obscure the surface

filled: (of embryo) embryo fills the seed interior with the food reserves stored in the cotyledons; small amounts of endosperm may remain around the embryo

firm: texture—yielding under only moderately strong pressure; only slightly deformable without internal structural disruption

flanged: with a projecting rim or edge

flask-shaped: 3D shape—generally circular in cross-section, broadest at or below the middle, approximately globose below that and constricted above to a relatively narrow neck

fleshy: texture—fairly firm and dense, juicy or at least moist, and easily cut

floret: the unit of a grass spikelet consisting of a flower or caryopsis, with lemma and palea

foliate: appearing leaf-like

follicle: a dry to (rarely) fleshy fruit derived from a single carpel that opens along a single longitudinal suture; the seeds may be arillate or with a fleshy testa

foraminicidal: type of capsular dehiscence, fruits opening irregularly

funiculus: (alt. funicle) stalk connecting the ovule (later seed) to the ovary (later fruit) placenta

fusiform: spindle-shaped; broadest at the middle and tapering at both ends


geniculate: bent like a knee

gibbous: swollen on one side

glabrous: without hairs

glandular: texture—covered with small, raised secretory glands, regular or irregularly shaped, translucent or opaque, and maybe distinctly colored

glistening: sparkling with reflected light

globose: 3D shape—more or less spherical

glossy: shiny

glume: one of the (usually) two bracts at the base of a grass spikelet

granular: texture—having a grainy surface

grooved: texture—linear depressions that may be single or form a series of grooves over the surface

gynophore: stalk-like basal portion of the ovary, bearing the main body of the pistil at its summit


heart-shaped: 2D or 3D shape—one end has prominent double curved into two lobes, the other end angular or pointed

hemispherical: 2D shape—shaped like half a sphere

hilar: of or relating to a hilum

hilum: on seeds, the scar indicating where the funiculus was attached; on grass caryopses, the scar visible on the outer caryopsis surface revealing where the seed is attached on the inner fruit wall surface

hippocrepiform: 3D shape—horseshoe-shaped

honeycombed: surface texture where raised walls (a reticulum) surround depressed interspaces called interstices

horn: a straight or curved, slenderly conic or conoidal protrusion, resembling an animal horn

horseshoe-shaped: 3D shape—relatively slender and strongly compressed, the whole strongly curved over its length in a plane perpendicular to the direction of compression and forming an incomplete circle, the ends somewhat straighter than the rest and parallel or nearly so

hyaline: thin, membranous, and translucent or transparent

hypocotyl: portion of the embryonic axis below the cotyledons and above the radicle

hypostase: a disk of lignified tissue formed at the base of the ovule


incumbent: (of cotyledons) having the dorsal side of one cotyledon resting against the radicle

indehiscent: not opening on its own, as in a fruit

indurate: texture—hardened or stony; yielding under strong pressure; not deformable without internal structural disruption

infructescence: mature (fruiting) inflorescence

integument: ring-like or hood-like structure(s) that envelopes the nucellus, at maturity is the layers of the seed coat

internode: portion of a stem between two nodes

involucre: in the grasses, a whorl or cluster of bracts or bristles subtending a floret or spikelet

isthmus: (pl. isthmi) a narrow strip of tissue connecting two larger parts


keel: a longitudinal ridge, like the keel of a boat, formed by the lengthwise folding of a structure, such as a lemma or palea

kidney-shaped: 2D shape—broadly elongate and with one margin convex and the opposite side concave, each end bluntly rounded

knotted: 3D shape—a cylindrical or ellipsoid body that is swollen and constricted at intervals; torulose


lanceolate: 2D shape—lance-shaped; much longer than wide, with widest point below the middle, tapering to the apex (compare oblanceolate)

lanceoloid: 3D shape—lanceolate

lateral: (of embryo) embryo lies along the side of the seed, generally towards one end; of, at, or from the side; in grasses, can refer to the sides adjacent to the dorsal and ventral sides

leathery: texture—moderately thick, tough, and very pliable

legume: a usually dry, dehiscent fruit derived from a single carpel that opens along two longitudinal sutures

lemma: in grasses, the lower of the two bracts subtending the flower or caryopsis (compare palea)

lens: a mound, pad, or area of tissue situated near the hilum on seeds in the Mimosoideae and Caesalpinioideae

lens-shaped: 2D shape—round and flattened with two curved (convex) surfaces

lenticular: 3D shape—lens-shaped; biconvex

ligneous: woody

linear: (shape) long, narrow, and uniform in width; (of embryo) embryo is straight and much longer than wide

loculicidal: type of capsular dehiscence, opening longitudinally through the locules (compare septicidal)

loment: a usually dry fruit derived from a single carpel that breaks transversely into one-seeded fruit segments

lomentoid: resembling a loment

longitudinal: of or relating to length or the lengthwise dimension

lustrous: semiglossy


macropodous: an embryo having an enlarged or elongated hypocotyl

marginal: at, on, or close to the margin or border

mealy: loose, dry, and disintegrating in finely granular pieces like meal or flour

membranous: texture—extremely thin, pliable, and fairly tough

mericarp: a one-seeded section (carpel) of a schizocarp, as in Apiaceae fruits (compare schizocarp)

mesocarp: the middle layer of the pericarp, if divided into layers

micropylar collar: collar shaped tissue at micropyle

micropyle: an opening in the integuments of an ovule usually acting as a passage for the pollen tube

mitaform: shaped like a child's mitten

monocarpellary: ovary or fruit having one carpel

monoecious: having separate male and female flowers on the same individual

mottled: with colored spots, streaks, or blotches of a different color

mucilaginous: resembling mucilage; moist and sticky

mucronate: terminating with a short, sharp, abrupt tip

mucronulate: diminutive of mucronate

multiple: fruit formed from several flowers clustered in one mass

multiseriate: occurring in more than one series

muricate: texture—rough with small, hard, sharp projections


nucellus: complex structure that produces and encloses the megagametophyte (embryo sac)

nut: a fairly large, indehiscent, dry fruit with a thick and bony wall surrounding a single seed

nutlet: ≈achene

nutritive tissue: tissue within the seeds that nourishes the developing embryo; such as endosperm, perisperm, or chalazosperm in angiosperms; megagametophyte in gymnosperms


obclavate: 3D shape—club-shaped, with attachment at or near the broad end (compare clavate)

obconic: 2D shape—cone-shaped, with attachment at or near the narrow end

obconical: 3D shape—inversely cone-shaped, with point of attachment at narrow end

obcordate: 2D shape—heart-shaped, with attachment at or near the narrow end (compare cordate)

oblanceolate: 2D shape—lance-shaped, with attachment at or near the narrow end (compare lanceolate)

oblate: depressed globose

oblique: in a slanting direction or position, neither horizontal nor vertical

oblong: 2D shape—much longer than broad with nearly parallel sides, corners are rounded

obovate: 2D shape—ovate or egg-shaped in outline, with attachment at or near the narrow end (compare ovate, ovoid)

obovoid: 3D shape—obovate

obpyramidal: 3D shape—pyramid-shaped, with point of attachment at or near narrow end (compare pyramidal)

obtriangular: 2D shape—inversely triangular, with point of attachment at narrow end

obtuse: with a blunt or rounded apex

opaque: not transmitting light

operculum: a dehiscent cap (or lid) of a seed or fruit that opens during germination or dehiscence

orbicular: 2D shape—circular in outline, 3D shape—globose

orthodox: (of seed) seed that can be dried to low moisture levels

oval: 2D shape—elongate, widest at the middle, and symmetrically convex-attenuate to rounded ends

ovate: 2D shape—egg-shaped in outline, widest point is towards one end of the organ, the other end tapers gradually, attachment at or near the broad end (compare obovate, ovoid)

ovoid: 3D shape—ovate

ovule: organ that contains the egg and after fertilization, becomes the seed


palea: in grasses, the uppermost bract enclosing the flower or caryopsis (compare lemma)

papery: papyraceous, chartaceous; very thin, pliable, and readily torn; like paper

papilla: a minute, distinct, broad-based projection, tapering to a rounded apex

papillate: texture—bearing minute, distinct, broad-based projections, tapering to a rounded apex

pappus: the modified calyx in the Asteraceae, composed of hairs, bristles, awns, or scales

partial: (of embryo) embryo occupies over one-quarter of the seed interior but less than full, with some endosperm present. Partial embryo size is common in families with spatulate, linear, and curved embryo shapes.

pedicel: the stalk of a flower

pedicellate: borne on a pedicel

peduncle: stalk of an inflorescence

perianth: collective term for calyx and corolla of a flower

pericarp: fruit wall or fruit coat

perigynium: a sac-like structure surrounding the ovary

peripheral: (of embryo) embryo is curved around the outer edge of the seed, near the seed coat

perisperm: seed nutritive tissue comparable to the endosperm, but derived from the nucellus (maternal tissue)

petal: a member of the inner envelope of a flower (corolla)

phytomelan: carbonaceous, opaque material that usually covers the seed coat to give it a black appearance, common in certain monocot families

pilose: having thin, soft, long hairs

pitted: texture—surface with small depressions in which the areas between the hollows do not take on the appearance of a true reticular net

placenta: surface of the ovary that bears ovules

plano-convex: 2D shape—flat on one side, convex on the other

pleurogram: a U-shaped line on both seed faces resulting from modification of the face of the ovule during seed development, present in some species' seeds in the Fabaceae subfamilies Mimosoideae and Caesalpinioideae

plumose: (of a hair or bristle) feather-like

polygonal: =angular

pome: an indehiscent, fleshy fruit in which the outer part is soft and the center contains papery or cartilaginous structures enclosing the seeds

poricidal: type of capsular dehiscence, fruit opening by pores or flaps (often near the top)

prismatic: like a prism; with sharp, definite angles and flat sides

puberulent : texture—(or puberulous) bearing minute, soft hairs

pubescent: texture—bearing hairs

punctate: texture—dotted with pits or with translucent, sunken glands or with colored dots, similar to pitted

punctiform: like a point

pustular: with small blisters or pustules

pyramidal: 3D shape—pyramid-shaped (compare obpyramidal)

pyrene: the hard inner portion of a drupe, consisting of a bony endocarp and an enclosed seed


quadrangular: 2D shape—four-sided, as in a square or rectangle


rachilla: the main axis of the spikelet in grasses

rachis: the main axis of the inflorescence in grasses or of a compound leaf (frond) in ferns or palms

radicle: the embryonic root of the embryo

raphe: a ridge or seam on the seed coat, formed by the portion of the funiculus united to the ovule wall in longitudinally curved ovules

recalcitrant: (of seed) seed cannot be dried below relatively high moisture levels

reniform: 2D or 3D shape—kidney-shaped

reticulate: texture—netted, raised walls or concave grooves forming a net-like surface pattern with flat, concave, or convex interspaces

revolute: with margins rolled downward, or to the lower side

rhombic: 2D shape—diamond-shaped in outline; having the form of a rhombus

ribbed: wide, prominent, linear ridges that are generally rounded and longitudinally situated on the surface

ridged: raised, thick ridges, sharp edged or rounded, usually in a series that may cover the entire surface

roughened: texture—having a small, stout, stiff, more or less acute protrusions

round: 2D shape—orbiculate; circular

rudimentary: (of embryo) embryo is small and fills less than a quarter of the seed and can be variable in shapes, such as linear, spatulate, or oval

rugose: =wrinkled

ruminate: testa or seed coat folded into the endosperm


samara: a winged, indehiscent, dry fruit containing a single (rarely two) seed(s)

sarcotesta: pulpy or fleshy outer layer of the seed coat, simulates aril

scabrate: texture—rough, having small, stout, stiff, more or less acute protrusions

scale: general term for short, thin, flat bracts or hairs

scaly: texture, covered with small, thin, fine scales or flakes that may be removable

scarious: dry, thin, membranous, non-green, more or less translucent

schizocarp: fruit formed from a single ovary, with fused carpels, with or without accessory tissue; splitting between locules to form distinct, indehiscent, usually one seeded segments; usually dry, rarely fleshy (compare mericarp)

sclerified: hardened

scutellum: the single, relatively large cotyledon of a grass embryo

sectoroid: 3D shape—a wedge-shaped slice taken from an ovoid or globose structure (2D shape, sector-shaped)

sepal: a member of the outer envelope of a flower (calyx)

septicidal: type of capsular dehiscence, opening longitudinally by separating between the septa of adjacent carpels

septum: (pl. septa) a dividing cross wall or partition

serrate: having a saw-toothed margin, i.e., a margin notched with toothlike projections

serrulate: a minutely serrate margin

sessile: attached without a stalk

shiny: uniformly reflecting a high proportion of incident light at all angles

silique: (includes silicle) a fruit derived from a 2-carpellate gynoecium in which the two halves of the fruit split away from a persistent partition (around the rim of which the seeds are attached)

simple: fruit formed from a single flower with one pistil, solitary carpel or several fused carpels

spatulate: 2D shape—like a spatula; rounded at the apex, with base long and tapered; (of embryo) embryo is straight with the cotyledons expanded to form the shape of a spatula or spoon

spherical: 3D shape—globose

spicule: a small, pointed, epidermal appendage

spikelet: basic unit of the grass inflorescence, commonly consisting of a pair of glumes and one to many florets

spiny: having slender, stiff, sharp projections oriented in the general plane of the structure

spongy: soft, light, discontinuous but cohesive, and somewhat resilient

square: 2D shape—geometric figure bounded by 4 straight sides of equal length and 4 90º-angles

staminodes: a modified, sterile stamen

star-shaped: (of fruit), having a distal aspect like the stylized shape of a star, usually found in aggregate versus simple fruit

stellate: star-shaped; with radiating branches

sterile: lacking male and/or female reproductive parts; also, not producing fruit or seed

stigma: the portion of the pistil receptive to pollen

stipe: a stalk

stipitate: borne on a stalk

striate: texture—texture, having fine, parallel lines, grooves or ridges

strophiole: appendage or outgrowth of seed coat near the hilum and micropyle

style: in a flower, the narrow and elongated part of the pistil between the stigma and the ovary; sometimes persisting in fruit

style base: remnant of a style, as at the apex of Asteraceae achenes

sub-: a prefix meaning slightly, somewhat, or nearly (used with a descriptive term), or below (used with an anatomical term)

subglobose: 3D shape—almost globose

succulent: texture—herbaceous and juicy, often thickened

sulcate: having one or more elongate, relatively narrow and shallow depressions or grooves

suture: a line of fusion; a seam

syncarp: fruit derived from fusion of numerous ovaries in a many-flowered inflorescence or a flower with numerous carpels


tawny: brownish-yellow; tan

teardrop-shaped: 2D shape—widest point is toward one end of the fruit, the other end tapers sharply to a pointed end

tepal: a member of the perianth, when it cannot be differentiated into a calyx and corolla

terete: approximately circular in cross section; width and thickness approximately equal

testa: seed coat

thick: having or being of relatively great depth

thin: having or being of relatively little depth

tomentellous: slightly tomentose

tomentose: pubescence that is bent and matted, forming a woolly coating; often the hairs are silver or gray-colored

transection: a cross section; representing a plane made by cutting across an organ at a right angle to its length

translucent: transmitting light uniformly and diffusely

transverse: lying, situated, or placed across

triangular: 2D shape—three relatively straight sides with distinct corners; more angular than teardrop-shaped

trichome: a hair or hairlike outgrowth of the epidermis

trigonous: 3D shape—having three faces that meet at distinct angles; triangular in outline

trilocular: (ovary or fruit) having three locules

truncate: terminating abruptly, as if cut straight across

tuberculate: texture—bearing small, warty, swelling, rounded, or variously shaped projections

tubuliform: having the form of a tube or cylinder


umbo: a rounded protuberance on both faces of some seeds in the Mimosoideae, such as those of Prosopis

undulate: wavy-margined

utricle: a small, indehiscent, dry fruit with a thin wall (bladderlike) that is loose and free from the seed


valve: in fruits, one of the parts into which a fruit separates at maturity

ventral: adaxial; of the side of an organ facing the axis (compare dorsal)

verrucose: texture—warty, covered with wart-like projections

villous: covered with long, soft, fine hairs

vitta: (pl. vittae) an oil or resin tube in the pericarp of many Apiaceae fruits


waisted: in grass caryopses, refers to an embryo visible on the caryopsis surface that is constricted in the middle

warty: texture—distinct, rounded projections that are large relative to the fruit size; tuberculate, verrucose

wedge-shaped: 2D shape—triangular and tapering to a point at the base

with hooks: bristles or spines with curved or backwards pointing tips, or with secondary bristles along their length

with spikes: thick outgrowths that have a flared base and are thicker than spines

woody: consisting mainly of indurate lignified tissues, characteristic of or resembling wood

wrinkled: texture—shallow, irregular folds and furrows covering the surface; appearing overall though crumpled and then spread out