/ Dictionary / Index F first-day cover: Meaning and Definition of Find definitions for: first'-day cov'er Pronunciation: (fûrst'dā", -dā'), [key] — Philately. Philately. a cover marked so as to indicate that it was mailed on the first day of issue of the stamp it bears and from one of the cities at which the stamp was issued on that day. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. First day first-degree Related Content Daily Word Quiz: acerbity Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language