/ Dictionary / Index T three-master: Meaning and Definition of Find definitions for: three-mast•er Pronunciation: (thrē'mas'tur, -mä'stur), [key] — n. Naut. a sailing ship with three masts. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. three-legged race Three Mile Island Related Content Daily Word Quiz: denizen Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language