1
a
b
: something resembling a spinal column or constituting a central axis or chief support
c
: the part of a book to which the pages are attached and on the cover of which usually appear the title and author's and publisher's names
2
: a stiff pointed plant process
especially
: one that is a modified leaf or leaf part compare prickle sense 1, thorn sense 1a
3
: a sharp rigid process on an animal: such as
a
: spicule
b
: a stiff unsegmented fin ray of a fish
c
: a pointed prominence on a bone
Cite this Entry
“Spine.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/spine. Accessed 3 Sep. 2026.
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