/ Dictionary / Index E err: Meaning and Definition of Find definitions for: err Pronunciation: (ûr, er), [key] — v.i. to go astray in thought or belief; be mistaken; be incorrect. to go astray morally; sin: To err is human. to deviate from the true course, aim, or purpose. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: err (Thesaurus) ERP errancy Related Content Daily Word Quiz: persevere Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language