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

AI should be "embedded in the key sectors of our industry and especially" in small- and medium-sized firms, the backbone of the German economy, to create "industrial added value and high-quality jobs", he said.

From Barron's • Apr. 22, 2026

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

From Salon • Apr. 14, 2026

“We tend to undervalue and I would say underinvest in those unsexy but important capabilities like the oilers, like the auxiliaries, like the tenders. It’s the quiet backbone of American naval power.”

From The Wall Street Journal • Apr. 10, 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 Wart’s legs had fused together into his backbone and his feet and toes had become a tail fin.

From "The Once and Future King" by T. H. White

Related Words

• foundation
• spine