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definitions

sea horse

or sea·horse

noun
  1. any fish of the genus Hippocampus, of the pipefish family, having a prehensile tail, an elongated snout, and a head bent at right angles to the body.
  2. a fabled marine animal with the foreparts of a horse and the hind parts of a fish.
  3. a walrus.

Origin of sea horse

1425–75; late Middle English sehors walrus; compare German Seepferd
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for sea horse

sea horse

noun
  1. any marine teleost fish of the temperate and tropical genus Hippocampus, having a bony-plated body, a prehensile tail, and a horselike head and swimming in an upright position: family Syngnathidae (pipefishes)
  2. an archaic name for the walrus
  3. a fabled sea creature with the tail of a fish and the front parts of a horse
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