Mĕr'māid, n.

noun

n. [Fr. mer, Lat. mare, the sea, and Eng. maid.] A fabled marine animal, having the upper part like that of a woman, and the lower like a fish; a sea nymph with a fish’s tail.

An illustration of a mermaid holding a hand mirror, with her tail submerged in the water.
Mermaid.