/ Dictionary / Index A accessorial: Meaning and Definition of Find definitions for: ac•ces•so•ri•al Pronunciation: (ak"su-sôr'ē-ul, -sōr'-), [key] — adj. accessory; supplementary. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: accessorial (Thesaurus) access method accessorius Related Content Daily Word Quiz: arid Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language