spine

Noun

WordNet 3.0

the series of vertebrae forming the axis of the skeleton and protecting the spinal cord“the fall broke his back”Synonyms: spinal column vertebral column backbone back rachis
any sharply pointed projectionSynonyms: spur acantha
a small sharp-pointed tip resembling a spike on a stem or leafSynonyms: thorn prickle pricker sticker spikelet
the part of a book's cover that encloses the inner side of the book's pages and that faces outward when the book is shelved“the title and author were printed on the spine of the book”Synonyms: backbone
a sharp rigid animal process or appendage; as a porcupine quill or a ridge on a bone or a ray of a fish fin

Spine \Spine\, n. [L. spina thorn, the spine; akin to spica a point: cf. OF. espine, F. ['e]pine. Cf. Spike, Spinet a musical instrument, Spinny.]

1.(Bot.) A sharp appendage to any of a plant; a thorn. [1913 Webster]

2.(Zool.) (a) A rigid and sharp projection upon any part of an animal. (b) One of the rigid and undivided fin rays of a fish. [1913 Webster]

3.(Anat.) The backbone, or spinal column, of an animal; -- so called from the projecting processes upon the vertebrae. [1913 Webster]

4.Anything resembling the spine or backbone; a ridge. [1913 Webster]