abaxial:  On the side that is away from the axis (in nutlets, the side facing outwards). (compare adaxial)

accumbent: (of cotyledons)  Having the radicle lying against the edges of the two cotyledons.

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:  On the side that is towards the axis (in nutlets, the side facing inwards). (compare abaxial)

adnate:  United to a part or organ of a different kind, as stamens attached to petals.

alveolate:  Honeycombed. See Texture Comparison Sheet.

annular:  Forming a ring.

antrorsely:  Curved or bent toward the apex. (compare retrorsely)

apex (pl. apices):  The “tip” of an organ, opposite the base and often narrower than the base.

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

apiculate:  Having a short but conspicuous point at apex.

apomixis:  Asexual reproduction through seeds that do not go through meiosis.

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

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

ascending:  Growing or directing upward.

asperulous:  Slightly rough.

attenuate:  Tapering gradually usually to a long slender point.

awl-like:  3D shape—short, narrowly triangular, and sharply pointed like an awl.

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

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.

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barbed:  With short, sharp, hair-like projections, as on awns or bristles.

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

barren:  Unfruitful (not producing a seed or caryopsis) in grasses.

basal:  At or pertaining to the point of attachment of an organ (i.e., where the organ is supported and the conduit through which
nutrition takes place).

beak (adj. beaked):  A usually firm, terminal appendage, sometimes tapered, as on some fruits of the Asteraceae or the style in

berry:  An indehiscent, few- to many-seeded fruit from a single pistil, in which the pericarp becomes entirely fleshy.

biconvex:  Convex on both sides or surfaces. See Shape Comparison Sheet.

bifid:  Two-lobed, two-cleft, or 2-fid (usually in reference to an apex).

bilobed:  Having two lobes (usually in reference to shape); bilobal. See Shape Comparison Sheet.

blunt:  Having a dull edge or end; not sharp.

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

bristle:  A stiff hair or hair-like structure.

bulbiferous:  Bearing or producing bulbs or bulbils.

bulbil:  A small bulb or bulb-like body produced on above ground parts, often functioning as an asexual propagule.

bur:  A spiny dispersal unit formed by a rough prickly husk surrounding seed(s) or fruit(s).

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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.

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

carpophore:  A slender prolongation of the floral axis bearing the carpels (as in the Apiaceae).

cartilaginous:  Tough and firm but flexible; like cartilage.

caruncle:  A localized outgrowth of the seed coat near the hilum of the seed in some members of the Euphorbiaceae; it functions
as an eliaosome.

caryopsis:  A dry, indehiscent, one-seeded fruit in which the seed coat is fused to the pericarp in the hilar region only, as in most

caudate:  Tapering to a long, tail-like appendage.

channeled:  With parallel grooves.

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

chartaceous:  Papery.

ciliate:  With a marginal fringe of hairs.

ciliolate:  Minutely ciliate.

circumscissile:  Splitting or opening along a circumference, with the top coming off as a lid, as in some fruits.

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

cobblestone-like:  A texture with raised interspaces and relatively lower reticulations. See Texture Comparison Sheet.

collateral:  Next to each other, side by side.

coma:  A tuft of hairs, often attached to the tip of seeds.

compressed:  Flattened.

concave:  With the surface curved inwards.

concavo-convex:  With one surface curved inwards and the opposite surface curved outwards; C-shaped. See Shape Comparison

conduplicate: (of cotyledons) Folded together, with the fold-line along the long axis.

convex:  With the surface curved outwards.

conic, conical:  3D shape—cone-shaped, attached at the broader end. (compare obconic)

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

coriaceous:  Leathery.

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

cotyledon:  A primary leaf of the embryo, as in those encased in the seed structure.

crenate:  Having a margin with low, rounded or scalloped projections.

cuneiform:  Narrowly wedge-shaped. See Shape Comparison Sheet.

cuneate:  2D shape—wedge-shaped with point of attachment at wide end. (compare obcuneate) See Shape Comparison Sheet.

cupule:  A cup-shaped part or structure.

cupuliform:  Shaped like a small cup.

cuspidate:  Tipped with an abrupt short, sharp, firm point (compare mucronate)

cylindrical:  Of, relating to, or having the 3D shape of a cylinder; tubular or rod-shaped.

cypsela (pl. cypselae):  An achene fruit derived from an inferior ovary, characteristic of plants in the Asteraceae.

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deciduous:  Falling off; not persistent.

dehiscent (v. dehisce):  A fruit or fruit segment splitting open at maturity to release its seed contents.

delineating:  Outlining; marking.

dentate:  Edged with tooth-like projections; toothed.

dimorphic:  Occurring in two forms.

dimpled:  A slight depression or indentation in a surface.

disarticulate:  To separate at a joint.

discoid:  Resembling a disc.

disseminule:  Detachable plant part capable of being disseminated and of propagating; commonly a seed or fruit.

distally:  Anatomically located far from a point of reference, such as an origin or a point of attachment. (compare proximally)

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

dorsiventral:  Pertaining to the dorsal and ventral surfaces.

drupe:  A fleshy, indehiscent fruit with a stony endocarp.

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eglandular:  Having no glands.

elaiosome:  A lipid and protein-rich fleshy structure attached to some seeds and fruits; it attracts ants which then disperse the
disseminule. Examples include the caruncle in the Euphorbiaceae, the aril (outgrowth of the funiculus) in the Fabaceae, and
the structure found at the base of some fruits in the Asteraceae.

ellipsoid:  3D version of elliptic.

elliptic:  2D shape—oval. Oblong-like with the 2 ends narrowing and more or less alike. See Shape Comparison Sheet.

emarginate:  With a shallow notch at apex.

embryo:  The minute, rudimentary plant contained within a seed.

endocarp:  The inner layer of the pericarp.

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

entire:  Without division.

epappose, epappous:  Having no pappus.

excurrent:  Projecting beyond the tip, as the midvein of the palea in grasses.

exocarp:  The outer layer of the pericarp.

exserted:  Thrusted or protruding outward, as in stigmas exposed beyond the petals.

extraneous:  Not constituting a vital element or part.

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falling entire:  Disjoining as a unit, as in the pappus of some Asteraceae.

farinaceous:  Having a mealy or powdery texture.

fascicle:  A bundle or cluster, as in bristles or hairs subtending some grass disseminules.

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

filiform:  Having the form of or resembling a thread or filament.

flabellate:  2D shape—fan-shaped.

flanged:  Surrounded with a projecting rim or edge.

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

follicle:  A dry, single-chambered fruit that splits along only one seam to release its seeds.

funiculus:  Stalk by which the ovule (later seed) is attached to the placenta in the fruit.

furrow (adj. furrowed):  The longitudinal channel between the ribs of a ribbed surface.

fusiform:  Spindle-shaped; broadest at the middle and tapering at both ends. See Shape Comparison Sheet.

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gaping:  Deep and wide opening.

geniculate:  Bent like a knee.

gibbous:  Swollen on one side.

glabrous:  Without hairs.

gland (adj. glandular):  An organ or a structure that secretes a substance. See Texture Comparison Sheet.

glistening:  Sparkling with reflected light.

globose:  3D shape—more or less spherical. See Shape Comparison Sheet.

glossy:  Shiny.

glume:  One of the (usually) two empty bracts at the base of a grass spikelet.

granular:  Having a grainy surface. See Texture Comparison Sheet.

grooved:  Having a long narrow furrow or channel.

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herbaceous:  Green and leaf-like in appearance or texture.

heteromorphic:  Differing from each other in size or form.

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.

hirsute:  Pubescent with coarse, stiff hairs.

hispid:  Rough with firm, stiff hairs; bristly.

hispidulous:  Minutely hispid.

homomorphic:  Similar looking forms.

honeycombed:  Surface texture where raised walls (a reticulum) surround depressed interspaces called interstices. See
Texture Comparison Sheet

hyaline:  Thin, membranous, and translucent or transparent.

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imbricate:  Overlapping in a regular pattern.

incised:  Having margins that are sharply and deeply indented.

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:  Hardened.

incostal:  Located between the ribs.

internode:  Portion of a stem between two nodes.

interspace:  The depression or area outlined by the reticulum on a reticulated seed coat.

interstice:  The depression or area outlined by the elevated reticulum of an alveolated or honeycombed seed coat.

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

involute:  Having the margins rolled inward. (compare revolute)

irridescent:  Producing a display of lustrous, rainbow-like colors.

isodiametric:  Having a similar diameter in all planes.

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keel (adj. keeled):  A longitudinal ridge formed by the lengthwise folding of a structure, such as in a lemma or palea; like
the keel of a boat.

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lanceolate:  2D shape—lance-shaped; widest point below the middle, tapering to the apex. (compare oblanceolate ) See
Shape Comparison Sheet.

lanceoloid:  3D version of lanceolate.

lateral:  Of, at, or from the side. In grasses, can refer to the sides adjacent to the dorsal and ventral sides.

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 of some Fabaceae.

lenticular:  3D shape—lentil-shaped; lens-shaped.

linear:  Long, narrow, and uniform in width. See Shape Comparison Sheet.

lingulate:  3D shape—tongue-shaped.

longitudinal:  Of or relating to length or the lengthwise dimension.

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marginal:  At, on, or close to the margin or border.

membranous:  Thin, flexible; like a membrane.

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

mesocarp:  The middle layer of the pericarp.

mottled:  With spots, streaks, or blotches of a different color than the base.

mucilaginous:  Resembling mucilage; moist and sticky.

mucronate:  Terminating with a short, sharp, abrupt tip. (compare cuspidate)

mucronulate:  Diminuitive of mucronate.

multiseriate:  Occurring in more than one series.

muricate:  Rough with small, hard, sharp projections.

muticous:  Blunt, without a point or spine, as in bracts that lack awns.


notch (adj. notched):  A V-shaped cut.

nutlet:  A one-seeded portion of a fruit that separates from the other portions (usually 4 total portions) when the fruit is

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

obconic:  3D shape—cone-shaped, with attachment at or near the narrow end. (compare conic)

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

obcuneate:  2D shape—wedge-shaped with point of attachment at narrow end. (compare cuneate).

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

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

oblong:  2D shape—much longer than broad with nearly parallel sides. See Shape Comparison Sheet.

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

obovoid:  3D version of obovate.

obpyramidal:  2D shape—pyramid-shaped, with attachment at or near the narrow end. (compare pyramidal)

obscure:  Faint.

obtrullate:  2D shape—trowel-shaped, with attachment at or near the narrow end. (compare trullate) See
Shape Comparison Sheet.

obtuse:  With a blunt or rounded apex.

olivaceous:  Olive-green.

opaque:  Impenetrable by light; neither transparent nor translucent.

orbicular:  2D shape—circular in outline. 3D shape—spherical. See Shape Comparison Sheet.

ovate:  2D shape—egg-shaped in outline, generally with attachment at or near the broad end. (compare obovate)
See Shape Comparison Sheet.

ovoid:  3D version of ovate.

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

pallid:  Lacking in radiance or vitality; dull.

papilla (pl. papillae):  A minute nipple-like projection on the surface.

papillate:  Bearing papillae. See Texture Comparison Sheet.

papilliform:  Shaped like a papilla.

pappose, pappous:  Having a pappus.

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

pectinate:  Having projections resembling the teeth of a comb; comb-like.

pedicel:  The stalk of a flower, inflorescence, or grass spikelet.

pedicellate:  Borne on a pedicel.

peduncle:  The stalk of a single- or multi-flowered inflorescence.

perianth:  Collective term for calyx and corolla of a flower.

pericarp:  The fruit wall.

perisperm:  Seed nutritive tissue comparable to the endosperm, but derived from the nucellus, which is maternal

petal:  A member of the inner envelope of a flower (i.e., corolla).

phyllary:  One of the involucral bracts subtending the flower head in the Asteraceae.

pilose:  Having thin, soft, long hairs.

pitted:  Surface with small depressions in which the areas between the hollows do not take on the appearance of
a true reticular net. See Texture Comparison Sheet.

placenta:  Place inside the ovary that bears ovules.

plano-convex:  2D shape—flat on one side, convex on the other; D-shaped. See Shape Comparison Sheet.

plumose:  Feather-like.

pod:  A dry fruit, typically dehiscent, elongated, and enclosing multiple seeds, as in fruits of the Fabaceae (e.g.,
legume) or Asclepias (e.g., follicle).

polygon (adj. polygonal):  A closed 2D figure bounded by four or more line segments. See Shape Comparison Sheet.

protruding:  Pushing or thrusting outward.

proximally:  Anatomically located close to a point of reference, such as an origin or point of attachment. (compare distally)

puberulent (or puberulous):  Bearing minute, soft hairs.

pubescent:  Bearing hairs. See Texture Comparison Sheet.

puckered:  Gathered into small wrinkles or folds.

punctate:  Marked with dots that are flat or sunken (pits).

puncticulate:  Minutely punctate.

punctulate:  Marked with small spots.

pustulate:  Having small, slight swellings that are not as abrupt as tubercles and are often at the base of hairs.

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

pyriform:  3D shape—pear-shaped.

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quadrangle (adj. quadrangular):   2D shape—four-sided, as in a square or rectangle.

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rachilla:  The main axis of the spikelet in grasses.

rachis:  The main axis of the inflorescence in grasses.

radicle:  The embryonic root of the embryo.

raphe:  The portion of the funiculus that is united to the ovule wall, commonly visible as a line or ridge on the
seed coat, as in some Brassicaceae.

rectangular-prismatic:  3D shape—a polyhedron based on rectangles.

reflexed:  Bent backward or downward.

remnant:  A portion of something that is left over; a remainder.

reniform:  Kidney-shaped. See Shape Comparison Sheet.

resin:  Any of numerous clear to translucent, yellow or brown, solid or semisolid, viscous substances of plant origin.

reticulate:  (n. reticulum):  In the form of a network; netted with interspaces. See Texture Comparison Sheet.

retrorsely:  Curved or bent toward the base. (compare antrosely)

revolute:  Having the margins rolled with the abaxial side outward. (compare involute)

rhombic:  2D shape—diamond-shaped in outline. See Shape Comparison Sheet.

ribbed:  Possessing narrow ridges with intervening furrows.

ridge (adj. ridged):  A long, narrow upper edge, angle, or crest of something.

round:  2D shape—circular. See Shape Comparison Sheet.

rugose:  Wrinkled. See Texture Comparison Sheet.

rugulose:  Finely wrinkled.

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scaberulous:  Rough to the touch because of minute projections.

scabrid:  Having a rough or scaly surface.

scabrous:  Having or covered with scales or small projections that are rough to the touch. See Texture Comparison Sheet.

scale:  General term for short, thin, flat bract or hair.

scarious:  Dry, thin, membranous, as in some bracts.

schizocarp:  A dry fruit that splits into two or more one-seeded indehiscent segments. (compare mericarp)

scutellum:  The single, relatively large cotyledon of a grass embryo.

sector-shaped:  2D shape—slice-of-pie-shaped. See Shape Comparison Sheet.

sectoroid:  3D shape—a wedge-shaped slice taken from an ovoid or globose structure. See Shape Comparison Sheet.

sepal:  A member of the outer envelope of a flower (i.e., calyx).

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

serrate:  Having a saw-toothed margin.

serrulate:  A minutely serrate margin.

sessile:  Attached without a stalk.

setae:  Bristles.

setose, setaceous:  Covered with setae; bristly.

sheath:  An enveloping tubular structure, such as the base of a grass leaf that surrounds the stem.

silicle:  A short pod-like dehiscent, 2-valvular fruit of the Brassicaceae, usually having a length less than three
times its width.

silique:  The pod-like, 2-valvular fruit of the Brassicaceae that is longer than broad.

spatulate:  Shaped like a spatula; rounded at the apex, with base long and tapered.

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

spinescent:  Terminating in a spine; spiny.

spinose:  Bearing spines; spiny.

stellate, stelliform:  Star-shaped; with radiating branches.

sterile:  Reproductive structures fail to develop sufficiently to produce viable fruit or seed.

stigmaticose:  Full of tiny points or marks, as in the microscopic marks on the seed surface of the genus Brassica.

stipe:  A stalk.

stipitate:  Borne on a stalk.

stippled:  Dotted.

striate:  Having fine, parallel lines, grooves, or ridges. See Texture Comparison Sheet.

strigose:  Having stiff, straight, closely-appressed hair.

striolate:  Minutely striate.

stylar:  Of, relating to the style.

style:  In a flower, the narrow and elongated part of the pistil between the stigma and the ovary.

stylopodium:  An enlargement at the base of the style in some members of the Apiaceae.

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

subapical:  At one side near apex of ovary.

subcoriaceous:  Slightly leathery.

subglobose:  Nearly globular.

subtend:  To occur beneath.

subulate:  Very narrow and tapering; awl-shaped; linear.

suture:  A line of fusion; a seam.

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tawny:  Brownish-yellow; tan.

tepal:  A member of the perianth when it cannot be differentiated into sepals and petals.

terete:  Approximately circular in cross-section.

testa:  Seed coat.

torulose:  A cylindrical or ellipsoid body that is swollen and constricted at intervals.

translucent:  Clear, transparent.

trapezoidal:  Shaped like a trapezoid with 2 nearly parallel sides and 2 angled sides.

transverse:  Lying, situated, or placed across.

trichome:  A hair or hair-like outgrowth of the epidermis.

trigonous:  Three-sided or triangular in cross-section.

trullate:  Trowel-shaped, generally with the attachment at or near the broad end. (compare obtrullate) See
Shape Comparison Sheet.

truncate:  Terminating abruptly, as if cut straight across.

tubercle (adj. tuberculate):  A small, smooth, rounded projection or excrescence (e.g., wart). See Texture
Comparison Sheet

turgid:  Tumid or swollen.

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umbonate:  Having or resembling a knob or knob-like protuberance.

undulate:  Wavy-margined.

utricle:  A dry, thin-walled fruit with a free single seed.


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

ventral:  Of the side of an organ facing the axis. (compare dorsal)

verrucose:  Covered with wartlike projections.

vestigial:  Minute; a remnant.

villous:  Covered with long, soft, fine hairs.

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wavy:  Uneven by virtue of having wrinkles or waves.

whorl:  A circular arrangement of like parts around a point on an axis, as in sepals of a flower.

wiry:  Resembling wire in form and flexibility.

withered:  Having lost all moisture, causing the collapse of some tissue.

woolly:  Covered with long, soft, whitish hairs.

wrinkle (adj. wrinkled):  A small furrow, ridge, or crease on a normally smooth surface, caused by crumpling,
folding, or shrinking. See Texture Comparison Sheet.

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