Entry 3 senses Webster, 1913

Acantha

/äk-än'-thə/ · A·can·tha · IPA /əˈkæn.θə/

01 n. A prickle.

1.
A prickle.(Bot.)
2.
A spine or prickly fin.(Zool.)
3.
The vertebral column; the spinous process of a vertebra.(Anat.)