A large evergreen tree, trunk 15-20 m tall, base often buttressed; branches whorled with bitter,milky juice; leaves 5-9 (usually 7) in a whorl, obovate, elliptic-oblong or oblanceolate, glabrous, obtuse or emarginate at apex, narrowed into short petiole at the base, nerves 30-60 pairs; flowers with unpleasant smell, in many flowered, pubescent, terminal or subterminal, umbellate cymes; peduncles 2-8 cm, very stout, rarely absent; flowers sessile or very shortly pedicelled; calyx eglandular, shortly 5-ribbed, lobes 5; corolla hypocrateriform, lobes 5, rounded, obovate-oblong, imbricate, throat villous with a ring of reflexed hairs; tube cylindric, greenish-white; disc absent; stamens 5, inserted near the top of the tube, included; filaments short; anthers ovate, acute; carpels 2, apocarpous; ovary hirsute; ovules many; style filiform; stigma minute, sometimes 2-lobed; fruit elongated, cylindric follicle, paired; seeds oblong or linear, flattened, peltately attached, comose at both ends.