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underthrust

American  
[uhn-der-thruhst] / ˈʌn dərˌθrʌst /

noun

Geology.
  1. a thrust fault in which the footwall moved and the hanging wall did not (overthrust ).


underthrust British  
/ ˈʌndəˌθrʌst /

noun

  1. geology a reverse fault in which the rocks on the lower surface of a fault plane have moved under the relatively static rocks on the upper surface Compare overthrust

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of underthrust

First recorded in 1890–95; under- + thrust

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

But we can now see that it's actually the weight of the ocean plates where they underthrust the continents that plays the major role in driving this remarkable system.

From BBC

He gave a quick underthrust of his sword, struck him midway of the body and raised the old man completely from the ground.

From Project Gutenberg