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

Four sophomores have been the backbone of the fourth straight 20-win season by San Diego State’s women’s basketball team. —Bill Center, San Diego Union-Tribune, 18 Feb. 2026

Other Republican senators finally grew some backbone and spoke out. —Kristen Monroe, Chicago Tribune, 17 Feb. 2026

The article comes on the heels of the weekend’s Munich Security Conference, where US Secretary of State Marco Rubio called on Europe to assume more responsibility for its own defense after relying for decades on Washington’s help as the backbone of its security. —Brad Lendon, CNN Money, 16 Feb. 2026

My backbone jumped a couple of feet sideways? —Andrew Fedorov, Travel + Leisure, 15 Feb. 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)