Meaning of four-eyed fish

four'-eyed fish'

Pronunciation: (fôr'ī", fōr'ī"). [key]
  1. a small, surface-swimming fish, Anableps anableps, inhabiting shallow, muddy streams of Mexico and Central America, having each eye divided, with the upper half adapted for seeing in air and the lower half for seeing in water.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.