Grewia optiva is a small to medium-sized deciduous tree, 9-12 m in height; crown spreading; bole clear, 3-4 m, and about 1 m diameter. Branches smooth, pale silvery-brown; bark dark brown, thick and roughish, exfoliating in small woody scales; blaze rather fibrous, pale yellow, often tinged pink towards the exterior, juice slimy. Leaves opposite, 5-13 cm x 3-6 cm, ovate, acuminate, closely serrate; teeth small, blunt; rough and hairy above, pubescent beneath, base rounded, slightly oblique, 3-nerved; petiole 0.3-1 cm long, stout, tomentose; stipules 0.5 cm long, linear subulate, caducous. Flowers 1-8, together; penducles solitary, leaf opposed or exceptionally a few axillary; tomentose, 0.8-1.8 cm long. Sepals 1-1.5 cm long, linear oblong, 3-ribbed, green outside, white, pale yellow or red inside; petals white or pale yellow, shorter than the sepals, linear, claw distinct. Fruit is a drupe, 1-4 lobed, each lobe about 0.8 cm in diameter, olive green then black when ripe. The genus was named after Nehemiah Grew, one of the founders of plant physiology.