/ Dictionary / Index F fifteenth: Meaning and Definition of Find definitions for: fif•teenth Pronunciation: (fif'tēnth'), [key] — adj. next after the fourteenth; being the ordinal number for 15. being one of 15 equal parts. —n. a fifteenth part, esp. of one (). the fifteenth member of a series. the interval of two octaves. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: fifteenth (Thesaurus) fifteen Fifteenth Amendment Related Content Daily Word Quiz: inutiae Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language