/ Dictionary / Index H hydrogen chloride: Meaning and Definition of Find definitions for: hy'drogen chlo'ride Pronunciation: [key] a colorless gas, HCl, having a pungent odor: the anhydride of hydrochloric acid. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. hydrogen bromide hydrogen cyanide Related Content Daily Word Quiz: vertigo Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language