Monoecious herbs or undershrubs, succulent, often with a rhizome or a tuber. Stem jointed. Leaves simple, alternate, stipulate, entire, toothed or lobed, often oblique. Flowers in bracteate cymes. Male flower: Perianth of 2 outer and 2 inner segments, opposite and decussate, valvate Stamens many, free or united. Female flower: Perianth of 2-5 segments, imbricate; staminodes absent or poorly developed; ovary 3(-1 to many)-locular, often angled or winged; styles 2-5, free or basally united; stigmas branched, twisted. Fruit a capsule or a berry. Seeds many, minute, oval or rounded.
The family has been placed near Cucurbitaceae. It resembles it in its branched stigmas, but differs in its leafy stipules and usually a winged or an angled ovary. It has also been placed near Datiscaceae by some authors.