/ Dictionary / Index A accession number: Meaning and Definition of Find definitions for: acces'sion num"ber Pronunciation: [key] the individual number or serial designation identifying specifically any of the items, as books or records, acquired by a library, collection, or the like. Cf. serial number. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. accession access method Related Content Daily Word Quiz: cautious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language