backbone

American  

[bak-bohn] / ˈbækˌboʊn /

noun

1. Anatomy. the spinal column; spine.

2. strength of character; resolution.

   Synonyms:

   fortitude, decision, firmness

3. something resembling a backbone in appearance, position, or function.

4. Bookbinding. a back or bound edge of a book; spine.

5. Nautical. a rope running along the middle of an awning, as a reinforcement and as an object to which a supporting bridle or crowfoot may be attached.

6. Naval Architecture. the central fore-and-aft assembly of the keel and keelson, giving longitudinal strength to the bottom of a vessel.

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backbone British  

/ ˈbækˌbəʊn /

noun

1. a nontechnical name for spinal column

2. something that resembles the spinal column in function, position, or appearance

3. strength of character; courage

4. the main or central mountain range of a country or region

5. nautical the main longitudinal members of a vessel, giving structural strength

6. computing (in computer networks) a large-capacity, high-speed central section by which other network segments are connected

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backbone Scientific  

/ băk′bōn′ /

1. See vertebral column

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backbone Cultural  

1. The primary line(s) that connects the slower, shorter cable portions of a communications network together. (See last mile.) In larger networks, such as the Internet, a backbone consists of high-capacity, high-speed lines that can extend over great distances.

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Other Word Forms

• backboned adjective
• backboneless adjective

Etymology

Origin of backbone

1250–1300; Middle English bacbon. See back ¹, bone ( def. )

Example Sentences

Those dense, umami-packed centers become the backbone of the dressing.

From Salon • Apr. 14, 2026

"But that's the reality of our theatre ecosystem, there are thousands of people working whose names you don't know, who are the backbone of British theatre."

From BBC • Apr. 12, 2026

They are often dismissed as a punch line, but Roxane Gay explains why women’s book clubs are the backbone of a passionate literary culture.

From Los Angeles Times • Apr. 9, 2026

The company has reportedly become Maven's primary technology contractor, and its AI now forms the operational backbone of the program.

From Barron's • Apr. 5, 2026

His arms were forged of steel, his backbone was the railroad, and in his veins was the coal that powered them both.

From "Ophie's Ghosts" by Justina Ireland

Related Words

• foundation
• spine