fault line

American  

noun

Geology.

• fault lines
  plural

1. the intersection of a fault with the surface of the earth or other plane of reference.

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fault line British  

noun

1. Also called: fault plane. geology the surface of a fault fracture along which the rocks have been displaced

2. a potentially disruptive division or area of contention

   Europe remains the main fault line in the Tory Party

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Other Word Forms

Noun Inflected Forms

• fault lines
  plural

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Etymology

Origin of fault line

First recorded in 1865–70

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Example Sentences

See Examples For:

fault line

The fault line is one of Southern California’s top seismic danger zones because it runs under dense and crowded areas.

From Los Angeles Times ● Sep. 6, 2026

It is a fault line that has divided Icelanders for decades, but after winning a snap election in 2024 Prime Minister Kristrún Frostadóttir's centre-left government pledged to hold a referendum by 2027.

From BBC ● Aug. 26, 2026

Playing a childless, vain, pitch-perfect vision of Los Angeles’ wickedness in “Maps to the Stars,” Julianne Moore mothered so hard she almost separated California right down the San Andreas fault line.

From Salon ● May 10, 2026

The episode exposed a fault line in Silicon Valley between engineers who viewed autonomous targeting as an ethical red line and defense officials who saw it as essential.

From Barron's ● Apr. 5, 2026

But a fault line ran through the center of his thinking, a kind of mysterious region where ideas entered going in one direction but then emerged headed the opposite way.

From "Founding Brothers: The Revolutionary Generation" by Joseph J. Ellis

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Related Words

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