Apostate

Part of speech: noun (n.)

1. One who has forsaken the faith, principles, or party, to which he before adhered; esp., one who has forsaken his religion for another; a pervert; a renegade.

2. One who, after having received sacred orders, renounces his clerical profession.

Part of speech: verb (v.)

To apostatize. [Obs.] We are not of them which apostate from Christ. Bp. Hall.

Part of speech: adjective (a.)

Pertaining to, or characterized by, apostasy; faithless to moral allegiance; renegade. So spake the apostate angel. Milton. A wretched and apostate state. Steele.