/ Dictionary / Index H H.I.H.: Meaning and Definition of Find definitions for: H.I.H. Pronunciation: [key] His Imperial Highness; Her Imperial Highness. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. high yellow Hiiumaa Related Content Daily Word Quiz: supercilious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language