A*pos"ta*sy (#), n.; pl. Apostasies (#). [OE. apostasie, F. apostasie, L. apostasia, fr. Gr. a standing off from, a defection, fr. to stand off, revolt; from + to stand. See Off and Stand.]
An abandonment of what one has voluntarily professed; a total desertion of departure from one's faith, principles, or party; esp., the renunciation of a religious faith; as, Julian's apostasy from Christianity.
© Webster 1913.