/ Thesaurus / H Synonyms of hydroxyl ion Find synonyms for: Noun1. hydroxide ion, hydroxyl ion, anionusage: the anion OH having one oxygen and one hydrogen atomWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: inutiae Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language