Turmeric is the underground stem of a ginger-like plant (rhizome).
Turmeric underground stem:
Turmeric's subterranean stem is known as a rhizome, and it is divided into two parts: the core pear-shaped mother rhizome and the lateral axillary branches known as fingers.
They are usually found as a brilliant yellow, fine powder in the ground.
Turmeric has a rough, segmented surface and is a tuberous rhizome.