noun
apostasy; renunciation of faith; defection from a religion
Primarily used for abandoning or renouncing a religious belief or affiliation. Can also refer to ideological defection.
彼はキリスト教からの背教を宣言した。
He declared his apostasy from Christianity.
背教は一部の国では死刑に値する罪とみなされる。
Apostasy is considered a capital offense in some countries.