/ Dictionary / Index A antiarrhythmic: Meaning and Definition of Find definitions for: an•ti•ar•rhyth•mic Pronunciation: (an"tē-u-ri'mik, -u-rith'-, an"tī-), [key] — Pharm. Pharm. —adj. of or pertaining to any substance that prevents, inhibits, or alleviates heartbeat irregularities. —n. any such substance, as lidocaine. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: antiarrhythmic (Thesaurus) antiar antiart Related Content Daily Word Quiz: fresco Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language