fault line

American  

noun

Geology.

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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Etymology

Origin of fault line

First recorded in 1865–70

Example Sentences

Thanks to their location close to tectonic plate fault lines, South Pacific islands are surrounded by potentially enormous mineral deposits.

From The Wall Street Journal

"This is significant because it means the ground shaking near the fault line might be more intense than our current hazard models predict for these types of faults."

From Science Daily

A clarion call for diplomacy and cooperation, it reminded me that it is not only in humanity’s interest to avoid ultimate conflict but our moral duty to bridge the fault lines between our civilizations.

From The Wall Street Journal

And it might exacerbate fault lines that are already starting to show within the party.

From BBC

He cited safety concerns—the plant sits on a fault line.

From Barron's

Related Words

• rift