/ Dictionary / Index M medusa: Meaning and Definition of Find definitions for: me•du•sa Pronunciation: (mu-d'su, -zu, -dy'-), [key] — pl. -sas, -sae a saucer-shaped or dome-shaped, free-swimming jellyfish or hydra. Me•du•sa Pronunciation: (mu-d'su, -zu, -dy'-), [key] — pl. -sas. the only mortal of the three Gorgons. She was killed by Perseus, and her head was mounted upon the aegis of Zeus and Athena. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: medusa (Thesaurus) medullation medusafish Related Content Daily Word Quiz: censure Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language