/ Dictionary / Index M mayfly: Meaning and Definition of Find definitions for: may•fly Pronunciation: (mā'flī"), [key] — pl. -flies. Also calledany insect of the order Ephemeroptera, having delicate, membranous wings with the front pair much larger than the rear and having an aquatic larval stage and a terrestrial adult stage usually lasting less than two days. an artificial fly made to resemble this insect. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: mayfly (Thesaurus) Mayflower compact mayhap Related Content Daily Word Quiz: blanch Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language