/ Dictionary / Index A alluvion: Meaning and Definition of Find definitions for: al•lu•vi•on Pronunciation: (u-l'vē-un), [key] — n. a gradual increase of land on a shore or a river bank by the action of water, whether from natural or artificial causes. overflow; flood. alluvium. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: alluvion (Thesaurus) alluvial plain alluvium Related Content Daily Word Quiz: nonchalant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language