among the poets, a horse imagined to have wings; being that whereon Bellerophon was fabled to be mounted when he engaged the Chimera. See Chimera.

The opening of the fountain Hippocrene on mount Helicon is ascribed to a blow of Pegasus's hoof. It was feigned to have flown away to heaven, where it became a constellation. Hence

in astronomy, the name of a constellation of the northern hemisphere, in form of a flying horse. See Astronomy, No. 406.