| Noun | 1. | genus Cynancum - genus of perennial tropical African lianas dicot genus, magnoliopsid genus - genus of flowering plants having two cotyledons (embryonic leaves) in the seed which usually appear at germination Asclepiadaceae, family Asclepiadaceae, milkweed family - widely distributed family of herbs and shrubs of the order Gentianales; most with milky juice cynancum - any of various mostly giant tropical lianas of Africa and Madagascar having greenish or purple flowers and long smooth pods; roots formerly used as an emetic |