tuberiform Definition

tuber
noun

1a. bot.
A swollen rounded underground stem or rhizome, such as that of the potato, where food is stored allowing the plant to survive from one growing season to the next, and which may also have buds or ‘eyes' on the surface which can develop into new plants;
1b. bot.
A similar structure that is formed from a root, eg that of a dahlia.
2. anatomy.
A thickened region or swelling.

Derivative: tuberiferous
adj

Etymology: 17c: Latin tuber a swelling.