Deciduous or semi-deciduous tree up to 20(–25) m high, with a spreading, rounded crown, rarely a low shrub 1.5–2 m high; trunk to 1.3 m in diameter, fluted; bark usually smooth, yellowish-brown, mottled or grey, but sometimes becoming rough, splitting longitudinally dividing into small, dark grey sections; branchlets and spines pubescent or finely puberulous, eventually glabrescent, the branchlets yellowish- to greyish-green, often becoming black on one side or in patches in the second year, sometimes deciduous leaving a swollen, woody scar. Spines axillary or rarely up to 5 mm above the axil or on older wood, (1–)3–6(–15) cm long, spines on flowering shoots usually absent or simple and 3–5 mm long, otherwise frequently branched, occasionally more than once, often appearing forked. Leaves with stipules persistent, triangular, 1–3 mm long, 0.8–1.5 mm wide; petiole 0.8–5 cm long; petiolules 0.1–2.5 cm long; leaflets elliptic to broadly ovate or suborbicular, 2.4–12 cm long, 1.5–9.7 cm wide, usually asymmetrical, apex rounded, obtuse, acute to apiculate or shortly acuminate, base rounded or broadly cuneate, becoming coriaceous, glabrous or variably pubescent on both surfaces, eventually glabrescent; foliole 2–3 mm long, usually linear, eventually caducous. Inflorescence a (1–)3–7-flowered subfasciculate or umbellate cyme, 1–2 in a leaf-axil of 1-year old stems or several on an axillary, often leafy, shoot, variably tomentellous to pubescent or puberulous, indumentum yellowish-green to buff; peduncle absent or up to 1 cm long; pedicels 0.3–1.3 cm long. Flowers 5-merous, often scented, sepals and petals reflexed after anthesis; sepals yellowish-green, ovate to obovate, 4–5.6 mm long, 2–3.2 mm wide, acute or rounded, tardily caducous, pubescent or densely puberulous outside, the glabrous margin broad; petals green or greenish-yellow, oblong-lanceolate to oblanceolate, 5–9 mm long, 1.5–2.5 mm wide, frequently with a contorted and glabrous tip, villous within; stamens 10, spreading, erect, anthers 1.2–1.9 mm long; ovary densely and stiffly hairy, 1 mm high; style 0.5–1.5 mm long. Fruit, usually one developing from an inflorescence, pale to reddish-brown when mature, oblong-ellipsoid to cylindrical and depressed at both ends or ovoid, 3.5–8 cm long, 2.2–3.7 cm wide, obtuse apically, often with 5 shallow grooves, elongating in early development, glabrous, eventually with a brittle surface, spongy and fibrous, dark and oily within with a hard cream-coloured endocarp; seed ellipsoid to fusiform, grooved, cream, up to 2.5 cm long, becoming loose in the mature fruit.
