- 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.
- a fabled marine animal with the foreparts of a horse and the hind parts of a fish.
- a walrus.
- 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)
- an archaic name for the walrus
- a fabled sea creature with the tail of a fish and the front parts of a horse