/ Dictionary / Index H heartbeat: Meaning and Definition of Find definitions for: heart•beat Pronunciation: (härt'bēt"), [key] — n. Physiol. a pulsation of the heart, including one complete systole and diastole. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: heartbeat (Thesaurus) heart back heart block Related Content Daily Word Quiz: simian Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language