/ Dictionary / Index H Hadrian IV: Meaning and Definition of Find definitions for: Hadrian IV. Pronunciation: [key] See Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Hadrian III Hadrian V Related Content Daily Word Quiz: sequester Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language