abaxial: of the side or
surface of an organ, facing away from the axis.
abscission: the normal shedding
from a plant of an organ that is mature or aged, e.g. a ripe fruit, an old
aciculate: needle-shaped, very
acuminate: tapering gradually
to a protracted point.
acute: terminating in a
distinct but not protracted point, the converging edges separated by an angle of
less than 90 degrees.
adaxial: of the side or
surface of an organ, facing towards the axis.
alternate: with one leaf or
other organ per node.
annual: a plant completing its
life cycle within one year.
anther: the pollen-bearing part
of a stamen.
antrorse: bent, and pointing
towards the apex.
apex: tip of an organ. adj.
appressed: pressed closely
against a surface (or another organ) but not united with it.
aquatic: living in or on water
for all or a substantial part of its life span.
arachnose: with soft, slender,
entangled hairs like a spider's web.
arcuate: curved like a
areolate: of surface pattern
or venation, divided into many angular or squarish spaces.
ascending: growing erect after
an oblique or semi-horizontal beginning.
asperulous: slightly rough to
auricle: an ear-shaped
appendage at the base of a leaf.
awn: a bristle-like appendage,
e.g. on the back of the lemma of a grass floret.
axis: a stem (commonly used for
the main stem of a whole plant or of an inflorescence).
bamboo: grasses classified
within the subfamily Bambusoideae, including the woody (Bambuseae) and
herbaceous (Olyreae) tribes.
basal: at the base.
biennial: a plant whose
life-span extends for more than one but less than two years after germination,
usually flowering in the second growing season.
bigeniculate: bent twice
geniculately (abruptly like a knee joint).
bisexual: bearing both male and
female functional organs together in the same flower.
blade: the part of the leaf
apical to the sheath, usually flattened, expanded.
bract: a leaf-like structure,
different in form from the foliage leaves and without an axillary bud,
associated with an inflorescence or spikelet.
bristle: a stiff, strong
callus: the hard, usually
pointed base of the spikelet (as in Heteropogon, Andropogon, and
related genera) or of the floret (as in Aristida and Austrostipa),
just above the point of disarticulation. In the former case, the callus is a
portion of the rachis; in the latter, it is a portion of the rachilla. In
Eriochloa the callus is the thickened node and remnant first glume; in
Chrysopogon it is part of the pedicel. adj. callose.
capillary: of hairs
etc., very slender.
cartilaginous: tough but
cataphyll: closely overlapping modified leaves at the base of a culm.
caryopsis: see grain.
caudate: having a narrow tail-like appendage.
cauline: of leaves,
borne on an aerial stem.
chartaceous: thin and
ciliate: fringed with
collateral: situated side by
side; adjacent and on the same radius of an axis.
column: the lower part of an
awn, when distinctly different from the upper part (sometimes twisted).
coma: hairs at the apex of the
lemma that are longer than, but otherwise similar to, those on the lower portion
of the lemma (Jacobs et al. 1995).
compound: of an
inflorescence, with several orders of branching.
connate: fused to another organ
(or other organs) of the same type; of pedicels, often fused to axis or
branch of inflorescence.
conduplicate: folded together,
with the fold-line along the long axis.
coriaceous: leathery and
corona: a cup-like structure
that appears to have been derived from the fusion of bulbous-based apical lemma
hairs (Jacobs et al. 1995).
culm: stem bearing the
cuspidate: tapering into a
sharp, rigid point.
deciduous: falling at the end
of the growth period or at maturity.
decumbent: of stems,
spreading horizontally, with the apex growing upwards.
decurrent: having the leaf base
prolonged down the stem as a winged expansion or rib.
deflexed: bent abruptly
dendroid: tree-like in form but
not in size.
diclinous: having the stamens
and carpels in separate flowers.
digitate: branching from the
axis or stalk like the fingers of a hand.
dioecious: having the male and
female reproductive structures on different plants.
disarticulation: separating at
a joint, e.g. florets in a spikelet.
plate or rim of tissue.
distal: remote from the point of origin or attachment.
dorsal: of a lateral
organ, (relating to the side) facing away from the axis, i.e. the 'back' or
eciliate: without marginal
effuse: spreading out,
elliptic: oval in outline,
widest at the centre.
emarginate: having a broad,
shallow notch at the apex.
entire: having a smooth margin,
not dissected or toothed.
ephemeral: short-lived, e.g. a
desert grass completing its lifecycle quickly after rain.
erect: upright; of a
margin, perpendicular to the plane of the rest of the organ.
erose: of a margin,
finely and irregularly eroded or incised.
excurrent: extending beyond the
margin or tip, usually refers to a midnerve developed into an awn or
extravaginal: of a
shoot, arising from an axillary bud which breaks through the sheath of the
fastigiate: parallel and erect;
usually of clustered branches and stems.
fertile: provided with
functional sexual parts which are capable of fertilisation and seed production;
in female-fertile floret, a floret capable of bearing a seed.
flexuous: bent from side to
side in a zig-zag form.
floret: a grass flower,
together with the lemma and palea that enclose it
geniculate: bent abruptly like
a knee joint.
glabrous: without hairs.
glaucous: a bluish-green
surface colour, often caused by having a whitish, waxy, powdery bloom on the
glume: a bract in the
inflorescence at the base of the spikelet (there are usually two).
grain: a one-seeded fruit, a
naked seed with a thin, free or adherent pericarp, often called a
granulose: covered with small
granules, finely mealy.
gynodioecious: having bisexual
flowers and female flowers on separate plants.
habit: the growth form of a
plant, comprising its size, shape, texture and orientation.
herbaceous: not woody, soft in
hirsute: bearing coarse, rough,
relatively long hairs.
hispid: bearing stiff, bristly
hyaline: translucent or
imbricate: closely packed and
incurved: bent or curved
inwards or upwards.
indumentum: the epidermal
appendages, e.g. hairs or scales, collectively.
indurate: hardened, often the
hardening developed only at maturity.
inflexed: bent sharply upward
inflorescence: the group or
arrangement in which spikelets are borne on a grass. An inflorescence is
subtended by a leaf or spatheole (sometimes absent). A group of inflorescences,
each subtended by a spathe or spatheole (sometimes termed a spatheate
inflorescence), is treated here as a synflorescence.
internode: the portion of a
stem between two nodes (the points at which leaves or branches of an
inflorescence arise on a stem).
involucre: a group (whorl) of
bracts or spikelets or other sterile structures, surrounding or subtending
spikelets and often shed with them.
involute: rolled inwards; of
a leaf, with the margins rolled towards the adaxial surface.
keel: a ridge like the keel of
laciniate: slashed into narrow,
parallel, pointed lobes.
lanceolate: lance-shaped, more
than about four times as long as broad, broadest in the lower half and tapering
towards the tip (narrowly ovate).
lateral: situated to a side,
e.g. the side of an axis.
lemma: the lower of two bracts
enclosing a grass flower.
ligule: a membranous or hairy
appendage on the adaxial surface of a leaf, at the junction between sheath and
linear: very narrow in relation
to the length, and with the sides parallel.
lobe: a projecting part,
usually one of two or more, each separated by a fissure or sinus.
lodicule: one of a pair of tiny
scales in a grass floret, between the lemma and the fertile parts of the flower,
which may be reduced perianth segments.
marginal: occurring at or very
close to the margin.
moniliform: cylindrical but
constricted at regular intervals like a string of beads.
monoecious: having the male and
female reproductive structures in separate flowers but on the same plant.
mucro: a sharp, abrupt terminal
point. adj. mucronate.
muricate: rough on the surface;
covered with short, hard tubercles or hard outgrowths of the epidermis.
muticous: without a point,
nerve: a vein of the glumes,
lemma or palea.
node: the level (transverse
plane) of a stem at which a leaf or inflorescence branch arises.
oblanceolate: similar in shape
to lanceolate but attached at the narrower end.
oblate: almost circular, but
with breadth slightly greater than the length.
oblong: having the length
greater than the width in the ratio of about 2:1 to 3:2, and the sides
obovate: similar in shape to
ovate but attached at the narrower end.
obsolete: reduced to a
rudiment, or completely lacking.
obtuse: blunt or rounded at the
apex, the converging edges separated by an angle greater than 90 degrees.
opposite: borne at the same
level but on opposite sides of the axis.
orbicular: circular or nearly
ovate: a two dimensional shape,
like a section through the long axis of an egg, and attached by the wider
palea: the upper of the two
bracts enclosing a grass flower.
panicle: a compound raceme; an
inflorescence in which the spikelets are borne on branches of the main axis or
on further branches of these.
papilla: a small, elongated
protuberance on the surface of an organ, usually an extension of one epidermal
cell. adj. papillose.
pedicel: the stalk of a
peduncle: the stalk of an
perennial: a plant whose
life-span extends over more than two growing seasons, fruiting more than
pericarp: the wall of a fruit,
derived from the ovary wall.
pilose: hairy, the hairs soft
and clearly separated but not sparse.
plicate: folded back and forth
longitudinally like a fan.
plumose: like a feather, with
fine hairs branching from a central axis.
proximal: near to the point of
origin or attachment.
prostrate: lying flat on the
puberulous: covered with
minute, soft, erect hairs.
pubescent: covered with short,
soft, erect hairs.
punctate: marked with
pungent: ending in a stiff,
raceme: an unbranched
inflorescence in which the main axis produces a series of spikelets, all
pedicellate, the oldest at the base and the youngest at the top.
rachilla: (= rhachilla) the
axis above the glumes in a grass spikelet.
rachis: (= rhachis) the axis of
rame: an unbranched
inflorescence in which the main axis produces a series of paired spikelets, one
sessile and one pedicellate, the oldest at the base and the youngest at the
recurved: curved or curled
downwards or backwards.
reflexed: bent sharply
downwards or backwards.
reticulate: forming a network
retrorse: bent, and pointing
away from the apex.
revolute: rolled downwards or
backwards; of a leaf lamina, with the margins rolled towards the abaxial
rhizome: an underground stem,
usually growing horizontally.
rib: a distinct nerve or linear
marking, often raised as a linear ridge, usually of leaves.
rudimentary: poorly developed
and not functional.
rugose: deeply wrinkled.
scaberulous: slightly or
minutely rough to the touch, minutely scabrous.
scabrous: rough to the
scale: a reduced or rudimentary
leaf; a thin flap of epidermal tissue; a thin scarious trichome which is
flattened and variously shaped.
scarious: dry and
sessile: without a
sericeous: silky, covered with
close-pressed, fine, straight silky hairs.
seta: a bristle or stiff hair.
setose: covered with
sheath: the lower portion of a
simple: undivided; of a
leaf, not divided into leaflets; of a hair or an inflorescence, not
sinus: a notch or depression in
the margin of an organ.
solitary: borne singly, not
spathe: a large bract,
ensheathing an inflorescence or its peduncle.
spatheole: a small bract or
spathe, ensheathing an inflorescence or its peduncle.
spike: an unbranched,
indeterminate inflorescence in which the spikelets are without stalks.
spikelet: a unit of the
inflorescence, usually consisting of two glumes and one or more florets (each
with palea and lemma between which the flower is borne).
spine: a stiff, sharp pointed
structure, formed by modification of a plant organ.
spinose: bearing spines.
stamen: one of the male organs
of a flower, consisting typically of a stalk (filament) and a pollen-bearing
sterile: lacking any functional
sexual parts which are capable of fertilisation and seed production.
stolon: a prostrate or trailing
stem that produces roots at the nodes.
striate: with parallel
longitudinal lines or ridges.
sub-: a prefix meaning nearly
subulate: narrow and tapering
gradually to a fine point.
synflorescence: an aggregation
of inflorescences. A group of inflorescences each subtended by a spathe or
terete: cylindrical or nearly
so, circular in cross-section.
terminal: at the apex or distal
trichome: an epidermal
outgrowth, e.g. a hair (branched or unbranched), a papilla.
trullate: a 2-dimensional
shape; resembling a trowel blade, i.e. with 4 straight sides with the axis
broadest below the middle and the length:breadth ratio between 3:2 and
truncate: with an abruptly
transverse end, as if cut off.
tubercle: a small wart-like
tuberculate: covered with
unilateral: grouped on one side
of an axis.
vernation: defined for Ausgrass
as the arrangement of a leaf when viewed in cross (transverse) section.
vestigial: reduced, minute or a
remnant, and no longer functional.
villous: shaggy with long, weak
whorl: a ring of leaves, bracts
or floral parts borne at the same level on an axis.
wing: a thin flange of tissue
extended beyond the normal outline.
woolly: very densely covered
with long, soft, more or less matted or intertwined trichomes, resembling