Trees, shrubs or rarely herbs, sometimes climbing by tendrils. Indumentum commonly of simple hairs, sometimes in tufts in the axils of leaf-veins, rarely fasciculate; glands of several kinds occurring on both vegetative and flowering parts. Leaves alternate, sometimes crowded (palm-like) at the apex of the tree, variously simple, ternate, biternate, pinnate or bipinnate, in the latter two kinds most often without a terminal leaflet at maturity; stipules lacking or small. Inflorescences axillary or cauliflorous, thyrsoidal, paniculate or racemose. Flowers regular or slightly zygomorphic, unisexual except in some Dodonaea but with non-functional organs of the other sex usually present. Calyx of (3–)4–5(−7) free or partially united imbricate or valvate sepals. Petals absent or 4–5, often with a basal claw, usually with a simple or elaborated scale on the inner face. Disk conspicuous, simple, or rarely a double ring, or reduced to a pair of glands. Stamens 5–20 (−74), often 8, but sometimes variable in number within a species, inserted in most cases inside the disk or occasionally on its surface; filaments free, terete or barely flattened, glabrous or hairy; anthers variously ovoid-sagittate to spherical, sometimes pilose, the connective rarely glandular, dehiscing introrsely by longitudinal slits; pollen grains tricolporate. Ovary 1–8-locular; ovules usually 1–2 (rarely several) per locule; style apical, except in Allophylus where semi-gynobasic, entire or 2–3-lobed. Fruit a capsule, sometimes lobed, or drupe, often composed of one matured mericarp with the aborted remaining carpels visible at its base. Seed usually with a hard black or brown testa, which in one case contains stomata, often with a conspicuous fleshy aril or sarcotesta, without endosperm.