noun /spaɪn/
a) A person or things backbone; the series of bones collectively from ones (literal or figurative) head to tail or pelvis.
If you attentively regard almost any quadrupeds spine, you will be struck with the resemblance of its vertebrae to a strung necklace of dwarfed skulls.
b) A rigid, pointed surface protuberance or needle-like structure on an animal, shell, or plant.
The male, as Dr. Gunther informs me, has a cluster of stiff, straight spines, like those of a comb, on the sides of the tail
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