1
2
: something that resembles a backbone: such as
a
: a chief mountain ridge, range, or system
b
: the foundation or most substantial or sturdiest part of something
c
: the longest chain of atoms or groups of atoms in a usually long molecule (such as a polymer or protein)
d
: the primary high-speed hardware and transmission lines of a telecommunications network (such as the Internet)
3
: firm and resolute character
4
Cite this Entry
“Backbone.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/backbone. Accessed 1 Sep. 2026.
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