/ Dictionary / Index F fifty-first: Meaning and Definition of Find definitions for: fif•ty-first Pronunciation: (fif'tē fûrst'), [key] — adj. next after the fiftieth; being the ordinal number for 51. being one of 51 equal parts. —n. a fifty-first part, esp. of one (). the fifty-first member of a series. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. fifty-fifty fifty-five Related Content Daily Word Quiz: languid Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language