Twining, woody vines, or climbing, rarely erect, shrubs, dioecious. Leaves alternate, entire; petiole swollen below the blade. Stipules wanting. Inflorescence consisting of axillary panicles or racemes. Flowers small, unisexual. Sepals 4—6 or more, free, imbricate in the bud. Petals 4—6 or reduced to 1, or wanting, free or connate. Sepals, petals and stamens usually each in 2 rows. Male flowers: stamens 6 and then epipetalous, or less; filaments free or united; anthers 4-celled or falsely so, longitudinally dehiscent. Female flowers: gynaecium of (1-)3—6 distinct, sessile or stipitate pistils, ovary superior, 1-celled, 1-carpelled; styles very short or wanting; stigma terminal, capitate or discoid, entire or lobed; staminodes 6 or wanting; ovules 2, one aborting, anatropous, on a parietal placenta; fruit a drupe; seed one, horseshoe-shaped; embryo long, curved; endosperm present or wanting. About 400 species in 63 genera, almost all tropical.