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seasnail

[see-sneyl]
noun, plural (especially collectively) sea·snail, (especially referring to two or more kinds or species) sea·snails.
  1. any of several snailfishes of the genus Liparis, of the North Atlantic.
  2. any of several marine gastropods having a spirally coiled shell, as a whelk.

Origin of seasnail

before 1000; Middle English seesnail, Old English sǣsnǣgl. See sea, snail
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for sea snail

sea snail

noun
  1. any small spiny-finned fish of the family Liparidae, esp Liparis liparis, of cold seas, having a soft scaleless tadpole-shaped body with the pelvic fins fused into a suckerAlso called: snailfish
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