seamount

[see-mount]
noun
  1. a submarine mountain rising several hundred fathoms above the floor of the sea but having its summit well below the surface of the water.

Origin of seamount

First recorded in 1945–50; sea + mount2
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for seamount

seamount

noun
  1. a submarine mountain rising more than 1000 metres above the surrounding ocean floorCompare guyot
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

Word Origin and History for seamount
n.

by 1908, from sea + mount (n.).

Online Etymology Dictionary, © 2010 Douglas Harper

seamount in Science

seamount

[sēmount′]
  1. A large underwater mountain, usually conical in shape and at least 1,000 m (3,280 ft) above the ocean floor. Seamounts are usually isolated and are volcanic in origin.
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