Small shrubs to large trees, less commonly lianas or herbs, glabrous or pubescent; schizogenous secretory canals throughout the plant body. Plants terrestrial, hemi-epiphytic, or climbing, evergreen or deciduous. Stems monocaulous or sparsely to well branched, usually pachycaulous. Leaves alternate (rarely opposite), frequently heteroblastic; petioles usually present (rarely sessile) and often sheathing at the base, sometimes alate, exstipulate, or with ligulate stipules; blade simple to ternately, palmately or pinnately lobed or compound (or peltate), with entire, crenate, toothed, or incised margins; venation pinnate or palmate. Mating system hermaphroditic or andromonoecious, rarely dioecious or diphasic. Inflorescences terminal (rarely axillary), paniculate, compound-umbellate or simple-umbellate, the ultimate units umbellate, capitulate, racemose, spikate, or rarely solitary; inflorescence axes subtended by foliose to minute bracts (or bracts lacking); flowers subtended by bracteoles (or bracteoles lacking). Flowers perfect, staminate, or pistillate, epigynous (rarely half-epigynous or hypogenous), actinomorphic. Perianth parts typically (3 or)5(–12). Calyx lobes simple and minute or obscure, but often forming a truncate rim. Petals valvate or imbricate, sometimes calyptrate, the bases broadly inserted. Stamens isomerous to several times the number of petals (3–250+), in one whorl (and then alternipetalous) to many whorls, anthers dorsifixed, introrse, tetrasporangiate (rarely octosporangiate), dehiscing by longitudinal slits; filaments filiform (to short and stout), inflexed in bud. Ovary syncarpous of 2–5(–100+) carpels (or unicarpellate through carpel abortion), each carpel unilocular with apical placentation; stigmas on a distinct style or sessile; styles free or connate, sometimes swollen at the base and confluent with the nectiferous disc of the ovary. Ovules anatropous, pendulous, one per locule, unitegmic, crassinucellate or rarely tenuinucellate. Fruits simple or sometimes multiple, fleshy (rarely dry), usually drupaceous or baccate with a fleshy mesocarp and a separate, variously sclerified endocarp (pyrene) around each locule, or rarely a schizocarp with two mericarps, with or without a free carpophore; one or more secretory canals (“companion canals” or “rib oil ducts”) found in association each vascular strand. Seeds straight; endosperm copious, oily, uniform or variously ruminate; embryo minute but well-differentiated.