backbone

American  

[bak-bohn] / ˈbækˌboʊn /

noun

backbones plural

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

Derived Forms

• backboned
  adjective
• backboneless
  adjective

Inflected Forms

Nouns

• backbones
  plural

Etymology

Origin of backbone

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

Example Sentences

Space Force awarded SpaceX a $2.29 billion fixed-price contract for its Space Data Network Backbone program.

From MarketWatch • May 27, 2026

The rocket and satellite company won a $2.29 billion fixed-price deal to contribute to what the Space Force called its Space Data Network Backbone program.

From MarketWatch • May 26, 2026

Baldy — which reaches 10,064 ft — is particularly dangerous during winter’s snowy conditions, especially on the challenging Devil’s Backbone Trail, which can expose hikers to heavy wind conditions.

From Los Angeles Times • Jan. 3, 2026

Climbers venturing along the Devil's Backbone trail are advised to carry crampons and ice axes.

From BBC • Dec. 31, 2025

Beyond the Milk of Hera, past the Backbone of Night, the mind of Democritus soared.

From "Cosmos" by Carl Sagan

Related Words

• foundation
• spine