noun

• (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.
  "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."
• (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.
  "Trademark Owners will nevertheless try to dictate how their marks are to be represented, but dictionary publishers with spine can resist such pressure."
• (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.
  "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."
• (botany) The heartwood of trees.