backbone

noun

back·​bone ˈbak-ˈbōn 

-ˌbōn

1

: spinal column, spine

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

: spine sense 1c

backboned

ˈbak-ˌbōnd 

adjective

Synonyms of backbone

• spine

Examples of backbone in a Sentence

She is the backbone of the family.

He showed some backbone by refusing to compromise his values.

Recent Examples on the Web

Chemical rockets, often associated with Goddard’s pioneering work but now encompassing a century of collective innovation, have been the backbone of space exploration. —Lee Billings, Scientific American, 18 Mar. 2026

The backbone would rely on hardened fiber, encrypted satellite links, and shared cyber intelligence feeds. —Judah Taub, semafor.com, 18 Mar. 2026

These short-form, mobile-first series are designed for speed, shareability and cultural specificity, with local casts and languages forming the backbone of production. —Faye Bradley, Variety, 17 Mar. 2026

Stretching more than 2,300 miles through 10 states, the Mississippi River forms the backbone of one of the most important economic corridors in America. —Beatrice Peterson, ABC News, 17 Mar. 2026

Word History

First Known Use

14th century, in the meaning defined at sense 1

Rhymes for backbone

• alone
• atone
• bemoan
• bluestone
• breastbone
• brownstone
• capstone
• cheekbone
• condone
• curbstone
• cyclone
• dethrone

Kids Definition

backbone

noun

back·​bone -ˈbōn 

-ˌbōn

1

: the skeleton of the trunk and tail of a vertebrate that consists of a jointed series of vertebrae enclosing and protecting the spinal cord

called also spinal column

2

: the foundation or sturdiest part of something

3

: firmness of character

a coward with no backbone

backboned

-ˈbōnd 

-ˌbōnd

adjective

Medical Definition

backbone

noun

back·​bone -ˈbōn, -ˌbōn 

1

: spinal column, spine

2

: the longest chain of atoms or groups of atoms in a usually long molecule (as a polymer or protein)