Deciduous:- Losing the leaves in the autumn.
Decumbent:- Lying along the ground, but with the tip ascending.
Decurrent:- Extending downwards; said of leaf or stipule edges when they continue down the stem as wings or raised lines.
Decussate:- Used of opposite organs (e.g. leaves), when alternate pairs are at right angles to each other
Deflexed:- Bent sharply downwards.
Dehiscent - Dehiscing:- Splitting open to release the seeds.
Deltate:- Shaped like an equal-sided triangle.
Edged with tooth-like projections; toothed.
Denticulate:- Finely toothed or notched; minutely dentate: minutely toothed.
Depressed:- Flattened from above.
Diadelphous:- In two bundles and united by the filaments.
Dichasium (pl Dichasia):- Cyme, with lateral branches on both sides of the main axis.
Dictostelic:- Relating to a vascular cylinder with large overlapping leaf gaps.
Dichotomous:- Forked, having the axis divided into two equal branches.
Didymous:- In pairs, divided into two lobes.
Didynamous:- Having four stamens arranged in two pairs of unequal length.
Diffuse:- Plants widely spread or scattered over an area, not concentrated in a definite and delimited place.
Digitate:- With finger-like lobes; generally refers to a leaf or bract.
Dimorphic:- With two different shapes or forms.
Dioecious:- With unisexual flowers, the male and female flowers on different plants.
Disk-floret:- The central florets of a flower-head which form a dis­tinctive disk, as in the flower-heads of many daisies.
Distichous:- In two opposite rows, one on each side of the stem.
Divaricate:- 1) Spreading wide; 2) In branching, densely branching, interlacing in three dimensions.
Dolabriform:- Hatchet-shaped.
Dorsifixed:- Of anthers, when the connective is attached between the base and apex of the filament.
Drupe:- A fleshy fruit with one or sometimes several seeds sur­rounded by a hard stone.