A‐pos″ta‐tize (�), v. i. [imp. & p. p.Apostatized (�); p. pr. & vb. n.Apostatizing.] [LL. apostatizare.] 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 �emblances.
Carlyle.