Extending downward; -- said of a leaf whose base extends downward and forms a wing along the stem.
a. (L. decurrere, to run down) extending downward, applied usually to leaves in which the blade is apparently prolonged downward as two wings along the petiole or along the stem.
a major tree form resulting from weak apical control. Trees with this form have several to many lateral branches that compete with the central stem for dominance resulting in a spherical or globose crown. Most hardwood trees have decurrent forms.