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
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
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
Online Etymology Dictionary, © 2010 Douglas Harper
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.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.