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.

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

n.late 15c., “walrus,” from sea + horse (n.); also see walrus. Also in heraldry as a fabulous animal withy the foreparts of a horse and the tail of a fish. Main modern sense in zoology is attested from 1580s.