Tall, slender, herbaceous or woody, climbing, dioecious perennial, herbs or shrubs with tuberous rhizomes, root-stocks or thick woody stem tubers. Leaves exstipulate, petiolate, alternate, rarely opposite, simple or compound; lamina variously shaped, multicostate, reticulate. Flowers bracteate, inconspicuous, in axillary spikes, racemes or panicles, unisexual, monochlamydous regular, actinomorphic. Male flowers: perianth 6-lobed, tubular at the base; stamens 6, in 2 series, or sometimes only 3, arising from the base of the perianth-tube. Female flowers: perianth 6, polyphyllous, persistent, superior; gynoecium tricarpellary, syncarpous ; ovary inferior, trilocular with axile placentation, rarely unilocular with parietal placentation, usually with 2 anatropous ovules in each locule; styles very short, free or connate; stigma terminal, simple or bifid, reflexed. Fruit a 3-winged, loculicidal capsule, sometimes a berry. Seeds often compressed and winged, endospermic.