apostatize

To renounce totally a religious belief once professed; to forsake one's church, the faith or principles once held, or the party to which one has previously adhered. He apostatized from his old faith in facts, took to believing in Carlyle.

Source: Webster's Revised Unabridged Dictionary (1913), United States public domain. See methodology for full licensing detail. Word validity for game play may differ from any official game dictionary.