spine

1. (anatomy, zootomy) A series of bones situated at the back from the head to the pelvis of a human, or from the head to the tail of an animal, enclosing the spinal cord and providing support for the thorax and abdomen.Examples: "If you attentively regard almost any quadruped's spine, you will be struck with the resemblance of its vertebrae to a strung necklace of dwarfed skulls."; "The preposterous altruism too! […] Resist not evil. It is an insane immolation of self—as bad intrinsically as fakirs stabbing themselves or anchorites warping their spines in caves scarcely large enough for a fair-sized dog."Synonyms: backbone, spinal column, vertebral column

2. (anatomy, zootomy) A series of bones situated at the back from the head to the pelvis of a human, or from the head to the tail of an animal, enclosing the spinal cord and providing support for the thorax and abdomen.Examples: "Trademark Owners will nevertheless try to dictate how their marks are to be represented, but dictionary publishers with spine can resist such pressure."Synonyms: backbone, spinal column, vertebral columnfiguratively

3. (zootomy, botany, mycology) A pointed, fairly rigid protuberance or needlelike structure on an animal, shell, mushroom or plant. The botanical term technically refers to such a structure derived from a leaf or part of a leaf.Examples: "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."Synonyms: needle, prickle, quill, spicule, spike, thorn, virgula

4. (botany) The heartwood of trees.

5. (neuroscience) Ellipsis of dendritic spine.Examples: "Spines are distinguished by the presence of globular tips called spine heads; when spines are present, the synapses innervating dendrites are made from these heads."abbreviationalt-ofellipsis

6. (geology) A tall mass of viscous lava extruded from a volcano.