Trees, shrubs or climbers, sometimes armed, bisexual, polygamous, monoecious or dioecious; stems usually prominently ringed with leaf-scars, usually unbranched or dichotomously branched. Leaves usually with sheathing base; petiole sometimes armed with spines (modified leaflets or epidermal emergences); blade pinnate, bipinnate, palmate or costapalmate (with the petiole extending into the leaf-blade as a well-defined central axis); leaflets induplicate or reduplicate, composed of one or more folds. Inflorescences axillary, single or occasionally grouped, often complex with bracteate branches of different orders, the ultimate branches bearing bracts subtending flowers, singly or in pairs, triads or small groups. Flowers usually small, bisexual, unisexual or sterile male, usually 3-merous; tepals sometimes similar, sometimes differentiated in calyx and corolla, free or fused. Stamens 3–many, free or united; anthers basi- or dorsifixed, straight or twisted; staminodes often present in female flowers. Carpels usually 1–3, free, or forming usually 3-celled ovary; ovule solitary in each carpel or cell; stigmas erect or recurved; pistillode often present in male flowers. Fruits usually 1-seeded, more rarely 2–10-seeded, usually with distinct epicarp (outer layer), mesocarp (middle layer) and endocarp (inner layer).