/ Dictionary / Index I illuvial: Meaning and Definition of Find definitions for: il•lu•vi•al Pronunciation: (i-l'vē-ul, i-lv'yul), [key] — adj. of or pertaining to illuviation or illuvium. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. illustrious illuviate Related Content Daily Word Quiz: simian Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language