/ Dictionary / Index S semper fi: Meaning and Definition of Find definitions for: sem•per fi Pronunciation: (sem'pur fī'), [key] — Informal. Informal. See Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Sempach semper fidelis* Related Content Daily Word Quiz: procrastinate Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language