Turmeric is a herbaceous perennial with a rhizome from which arises tufts of large, broad, lanceolate, bright green leaves acute at both ends.  The plant grows up to 60 to 90 cm high.  Leafy shoots are erect; bearing 6-10 leaves with the leaf sheath forming a pseudostem.  The ligule is a small lobe (1mm long).  The sheath near the ligule has ciliate margins. 

The inflorescence is a cylindrical spike, 10-55 cm long, and 5-7 cm wide and terminal on the leafy shoot.  The flowers are yellow or pale yellow, borne in a spike.  They arise from two buds situated in the axils of bracts and mature successively.  Bracts are greenish-white; the uppermost tinged with pink.  The bracteoles are thin and elliptic.  The calyx is short, unequally toothed and split nearly half way down on one side.  The corolla is tubular at the base and the upper half is cup-shaped.  There are two lateral staminodes.  The lip or labellum is obovate.  The ovary is inferior and trilocular with a slender style held by anther lobes and passing between them.  Fruits are seldom. 

The primary tuber at the base of the aerial stem is ellipsoidal bearing many rhizomes; straight or little curved, with secondary branches in two rows and further tertiary branches, the whole forming a dense clump.  Rhizomes have a distinctive taste and smell, brownish and scaly outside and the inside is bright orange in colour.  The roots are fleshy, often ending in a swollen starchy tuber.