The practice, act, or condition of being an apostate; renunciation of one's religious faith, political allegiance, or principles.
From apostate (from Late Latin apostata, from Greek apostates meaning 'rebellious') plus the suffix -ism. The suffix transforms the person (apostate) into the system or practice of apostasy.
During the Spanish Inquisition, apostatism—switching from Christianity to Islam or Judaism to survive—was one of the most dangerous choices anyone could make, yet many did it to save their families.
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