/ Dictionary / Index F FSR: Meaning and Definition of Find definitions for: FSR Pronunciation: [key] Field Service Regulations. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. FSO F star Related Content Daily Word Quiz: eccentric Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language