/ Dictionary / Index D deionize: Meaning and Definition of Find definitions for: de•i•on•ize Pronunciation: (dē-ī'u-nīz"), [key] — -ized, -iz•ing. to remove ions from. to reassociate the ions of (an ionized gas). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: deionize (Thesaurus) deinstitutionalize deipnosophist Related Content Daily Word Quiz: perspicacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language