/ Dictionary / Index I ISSN: Meaning and Definition of Find definitions for: ISSN Pronunciation: [key] International Standard Serial Number. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Issei issuable Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language