(v. i.) 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.

apostacize betray bolt break away change sides defect degenerate desert fall away fall off go over let down pull out rat renegade renege renounce repudiate run out on secede sell out switch switch over tergiversate turn turn against turn cloak turn traitor