°A winged
horse fabled to have sprung from the neck of
Medusa when she was slain. He is noted for causing, with a blow of his hoof, Hippocrene, the inspiring fountain of the
Muses, to spring from Mount Helicon.
Bellerophon rode Pegasus when he defeated the
Chimaera.
°An
autumn constellation of the
northern sky, near the vernal equinoctial point, said to resemble the mythical horse. Its three brightest stars, with the brightest star of
Andromeda, form the square of Pegasus. It contains the stars
Markab and
Algenib.