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

Nvidia’s graphics processing units have been the backbone of AI development thus far, but central processing units are having a moment.

From MarketWatch • Mar. 25, 2026

“He has been the backbone of our family,” said Maria, 56.

From The Wall Street Journal • Mar. 23, 2026

Most rides in jeepneys, the backbone of the country's transport system, were set to jump about eight percent on average, the regulator announced.

From Barron's • Mar. 17, 2026

These bonds create the backbone of countless substances including fuels, plastics and complex biological molecules.

From Science Daily • Mar. 14, 2026

Gilly could feel Miss Ellis’s fingers on her backbone gently prodding her through the doorway and into the house.

From "The Great Gilly Hopkins" by Katherine Paterson

Related Words

• foundation
• spine