Trees, shrubs, climbers or herbs, monoecious or dioecious, usually with milky latex. Leaves alternate or opposite, simple (in Australia), stipulate. Inflorescence axillary, unisexual or bisexual, a spike, raceme or with flowers in heads or enclosed within a fleshy receptacle. Flowers small, unisexual, perianth segments (2–)4(–8) or absent; stamens equal in number to the perianth segments, sometimes fewer; ovary superior to inferior, 1-locular; styles 1 or 2; ovule solitary. Fruit a small achene or nut, or drupe, often clustered into a multiple fruit.
About 53 genera with over 1400 species, mostly tropical with some temperate representatives; 7 genera and 47 species occurring in Australia.