/ Dictionary / Index S sergeant first class: Meaning and Definition of Find definitions for: ser'geant first' class' Pronunciation: [key] — U.S. Army. U.S. Army. a noncommissioned officer ranking next above a staff sergeant and below a first or master sergeant. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. sergeant at arms sergeantfish Related Content Daily Word Quiz: fidelity Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language