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.