spine

/spaɪn/

/spaɪn/

Other forms: spines

Your spine is your backbone. When you sit and stand with your spine straight, people will compliment you on your good posture.

Besides being the basic part of a vertebrate's skeleton, a spine is also a sharp spike, like the spines on a sea urchin or a cactus. Another kind of spine is the "backbone" of a book, the part of its cover that you can read when the book is on a bookshelf. Spine comes from the Latin spina, which also means both "backbone" and "thorn."

Definitions of spine

1. noun

   the series of vertebrae forming the axis of the skeleton and protecting the spinal cord
   synonyms: back, backbone, rachis, spinal column, vertebral column

   types:

   notochord

   a flexible rodlike structure that forms the supporting axis of the body in the lowest chordates and lowest vertebrates and in embryos of higher vertebrates

   chine

   backbone of an animal

   urochord

   a notochord of a larval tunicate typically confined to the caudal region

   type of:

   skeletal structure

   any structure created by the skeleton of an organism
2. noun

   any sharply pointed projection
   synonyms: acantha, spur

   type of:

   projection

   any solid convex shape that juts out from something
3. noun

   a sharp rigid animal process or appendage; as a porcupine quill or a ridge on a bone or a ray of a fish fin
   types:

   ray

   any of the stiff bony spines in the fin of a fish

   quill

   a stiff hollow protective spine on a porcupine or hedgehog

   type of:

   appendage, outgrowth, process

   a natural prolongation or projection from a part of an organism either animal or plant
4. noun

   a small sharp-pointed tip resembling a spike on a stem or leaf
   synonyms: pricker, prickle, spikelet, sticker, thorn

   types:

   glochid, glochidium

   a barbed spine or bristle (often tufted on cacti)

   type of:

   aculeus

   a stiff sharp-pointed plant process
5. noun

   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

   type of:

   part, portion

   something less than the whole of a human artifact