A merman, the male counterpart of the mythical female mermaid, is a legendary creature which is human from the waist up and fish-like from the waist down, but may assume normal human shape. Sometimes mermen are described as hideous and other times as handsome.

Merfolks, Mercreatures, Mermen or Merpeople are legendary water-dwelling human-like beings. They are attested in folklore and mythology throughout the ages in various parts of the world.