Glossary of plant parts (X returns to directory)

achene	small single seeded fruit that does not split (strawberry "seed") X
adventitious	roots or stems arising from unexpected locations
androecium	all of the stamens in a flower
anther	pollen-containing part of stamen, equivalent to microsporangium in a flower
axillary	in the axil, or in the angle between petiole and stem
berry	fleshy fruit with one or more seeds in the pulp, not enclosed in hard shell (grape)
bipinnate	pinnately divided leaf in which the leaflets are again pinnately divided (honey locust)
bract	a leaf-like structure with one or many flowers in its axil, often smaller than regular leaves and otherwise modified (scaly, brown or different shape)
bulb	underground structure with swollen leaf bases enclosing a bud
calyx	all of the sepals, often green and when present the outermost whorl of flower parts
capitulum	head of flowers attached directly to a flat disc or common receptacle (daisy family)
capsule	a dry fruit containing many seeds and opening by many pores or slits (poppy)
carpel	one section of an ovary, corresponding to a single sporophyll X
catkin	an inflorescence of many single-sex flowers without petals
chamaephyte	low growing plant with living structures visible all year round
cladode	stem structure more or less resembling a leaf, but in the axil of a reduced leaf (Asparagus fern has them)
compound leaf	divided into two or more leaflets (opposite of simple)
cordate	heart-shaped
corm	compressed underground stem, often enclosed in scale leaves
corolla	all of the petals, often colored, the next whorl in from the calyx in a complete flower
corona	tubular outgrowth usually from the petals (daffodil)
corymb	inflorescence in which pedicels branch at different points from the peduncle but flowers form a flat top
cotyledon	first seedling leaf or leaves
cyme	determinate inflorescence; ends with flower that opens first and later flowers arise as branches from the side
decussate	opposite leaves arranged so that each pair is at right angles to the one below X
dehiscence	opening or splitting of a fruit or anther
determinate	pattern of growth in which stem cannot continue growth, usually because it is terminated by a flower
dichotomous	branching into two equal structures (stems, veins etc.) leading to a"Y"
dioecious	male and female flowers on different plants
distichous	(usually alternate) leaves arranged in parallel rows along each side of stem
divided	leaf blade not entire but not compound (many oaks)
drupe	fleshy usually with one or few seeds enclosed in hardened inner wall of ovary (peach)
endosperm	storage tissue other than cotyledons in many seeds, formed by fertilization of central cell
entire	simple leaf with smooth margins, not compound or divided (elm)
epicotyl	the stem of a seedling or embryo between the cotyledons and the first true leaf
epigeal/geous	pattern of germination in which cotyledons remain below ground
epigynous	other floral structures attached above ovary, which is therefore inferior X
epiphyte	plant that grows on another plant
filament	stalk of stamen carrying anther
follicle	dry, many seeded fruit that splits along one side (milkweed)
fruit	mature ripened ovary of an angiosperm, usually developing after pollination of an ovary and containing seeds
geophyte	plant that overwinters by dying back to underground structure
glabrous	without hairs
glaucous	having a white waxy bloom
gynoecium	all of the pistils in a flower
helophyte	aquatic plant rooting at the bottom
hemicryptophyte	plant that overwinters by dying back to crown of buds at soil surface
hirsute	hairy all over
hydrophyte	free-floating water plant
hypocotyl	the part of an embryo or seedling between the radicle and the cotyledons X
hypogeal/geous	pattern of germination in which cotyledons remain below ground
hypogynous	other floral structures attached below the ovary, which is therefore superior
indehiscent	fruit that remains closed at maturity
indeterminate	growth pattern in which stem continues growth indefinitely
indusium	scaly covering over fern sporangia
internode	stem between nodes
involucre	overlapping bracts around an inflorescence
lamina	blade of leaf
leaflet	separate part of lamina of compound leaf
legume	dry, single chambered, multiseeded fruit dehiscing along two edges (beans and peas)
lenticel	pore in outer bark of woody plants
ligule	membranous outgrowth at junction of lamina and leaf sheath in many grasses X
linear	leaf at least 10 times as long as broad with parallel margins
locule	chamber containing seeds in an ovary
megaphyll	generally a large leaf with veins that are internally connected to the vascular system of the stem
microphyll	small leaf, without veins
monoecious	having separate male and female flowers on the same plant
monopodial	when growth continues through single apical meristem (which may periodically form dormant terminal buds)
nectary	nectar secreting gland in a flower, or on stem or leaf
node	part of stem where one or more leaves are attached
nut	hard, indehiscent, single-seeded fruit (filbert)
nutlet	small , single-seeded portion of ovary typical of Lamiaceae
palmate	compound leaf in which all leaflets attached at same point also pattern of veins radiating from the junction of the petiole and the lamina X
panicle	much-branched inflorescence
pappus	fine hairs replacing calyx in many asteraceae
pedicel	stalk of individual flower in an inflorescence
peduncle	stalk of inflorescence or of solitary flower
perianth	colective term for calyx and corolla
pericarp	ovary wall that becomes variously modified in fruits
perigynous	other floral structures attached to extension of the receptacle which partially encloses ovary
petal	single segment of the coralla
petiole	the stalk of a leaf, attaching the lamina to the node
phanerophyte	tall-growing plant with living structures visible all year
phyllotaxis	pattern of leaf arrangement on the stem; count from one leaf around the stem until meet another directly above; number of leaves/number of turns around stem X
pinnate	compound leaf with leaflets arrange along sides of common stalk also pattern of veins which branch from along a single mid-rib
pistil	collective term for ovary, style and stigma; the innermost structure in a complete flower
pome	fleshy fruit formed from the enlarged receptacle of a perigynous flower (apple)
pubescent	covered in soft, fine hairs
raceme	indeterminate inflorescence; individual flowers attached by pedicels along a common stalk
rachis	portion of pinnate leaf to which leaflets are attached
radicle	first (embryonic) root of seedling
rhizome	horizontal underground stem
sagittate	arrow-head shaped
samara	dry, winged, indehiscent fruit (ash)
scape	leafless peduncle arising from a basal rosette of leaves (dandelion) X
schizocarp	fruit that splits into single seeded portions
sepal	single segment of calyx, often green, but may be colored
sessile	not stalked (leaves and flowers)
silicle/silicula	flat dry fruit about as broad as long, splitting around edges to reveal seeds on papery central septum
silique	dry fruit longer than broad, splitting on two edges to reveal seeds on papery central septum
simple	leaves with a continuous lamina (opp. of compound)
sorus	cluster of sporangia on a fern leaf
spadix	a fleshy spike of numerous small flowers (typical of Araceae)
spathe	green, colored or dry sheath enclosing inflorescence (typical of Araceae)
spike	indeterminate inflorescence in which sessile flowers arise along a common stalk X
spikelet	small spike enclosed by bracts forming part of the inflorescence of many grasses and sedges
spine	sharp, needle-like modification of a leaf
sporophyll	modified leaf bearing sporangia
stamen	pollen bearing structures between corolla and pistil in complete flower
staminode	sterile stamens in some flowers
stigma	surface at end of style where pollination occurs
stipules	pair of outgrowths at base of petiole in some plants
strobilus	terminal cluster of sporophylls or cone
style	region of pistil between ovary and stigma, sometimes elongated
sympodial	when growth continues through a series of axillary branches that seem to form a single stem
tendril	part of stem, leaf or petiole that can coil around supporting structures X
tepal	a name given to a perianth segment when the distinction between sepals and petals does not seem to apply (e.g. when they are all colored)
testa	outer covering of a seed
thallus	plant body that is not differentiated into root, stem or leaf
tomentose	covered in short hairs
thorn	pointed modification of a stem
trichome	hair-like outgrowth
trifoliate/trifoliolate	compound leaf with three leaflets
tuber	underground stem or root
umbel	inflorescence in which all pedicels arise from the same point at the top of the peduncle
undulate	wavy (leaf) margins

Return to directory