Herbs, shrubs or trees, usually glabrous. Leaves alternate, entire, petiolate or sessile. Stipules minute, aculeolate or wanting. Inflorescence consisting of simple or compound, terminal or axillary racemes or panicles. Flowers hermaphrodite or unisexual. Perianth membranaceous or coriaceous, consisting of 4—5 tepals; the latter subequal or unequal. Stamens 3 to numerous, inserted on a hypogynous disc, irregular or biseriate, the outer cycle alternating with the tepals, the inner one epitepalous; filaments free or basically connate, filiform or subulate; anthers innate or versatile, bi-celled. Ovary superior, consisting of 1 to numerous, free or connate carpels; styles as many as the carpels, free or sometimes united; the ovules solitary in each carpel, campylotropous. Fruits 1- to many carpellary, samaroid, crustaceous or baccate; seeds erect, subglobose or subreniform; endosperm amylaceous. About 110 species in 22 genera, in tropical and subtropical regions, mostly in America.