Definify.com

Webster 1913 Edition

Adj.

Spinose; thorny.

Having the form of a spine or thorn; spinelike.

Spinous process of a vertebra

(Anat.)

the dorsal process of the neural arch of a vertebra; a neurapophysis.

Adj.

[L. spinosus, from spina.] Full of spines; armed with thorns; thorny.

spinous ‎(comparative more spinous, superlative most spinous)

Having many spines.
Spine-like; spiny.
Of a person, difficult to deal with, prickly.
Of a subject, providing many difficulties, thorny.
(anatomy) Having a sharp projection.
The spinous processes of the lumbar vertebrae.