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

Ultimately, Dick Cheney, the former backbone of the Republican Party, did the same. —Dana Taylor, USA Today, 21 Nov. 2025

The contract is part of a sweeping, years-long buildup to replace the aging Ohio-class submarines, the backbone of the US nuclear triad’s sea leg since the 1980s. —Kapil Kajal, Interesting Engineering, 19 Nov. 2025

Bogotá will begin detailed planning for infrastructure upgrades, pilot training and industrial-cooperation programs, paving the way for the Gripen to enter service later this decade as the backbone of the country’s future air-combat capability. —Amir Daftari, MSNBC Newsweek, 17 Nov. 2025

France has previously provided Kyiv with Mirage jets, which form the backbone of France’s aerial bomber force. —Joseph Ataman, CNN Money, 17 Nov. 2025

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)