The ancient criminal offence of heresy or non-belief in religion. (noun)
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Use "apostacy" in a sentence
"As there are numerous specifically 'moslem' states in the world where conversion to another religion (so called apostacy) attracts the death penalty I fail to see the moral authority behind those in the UN joining in calling Israel a 'racist state' yet no a tweet out of them on the fate of those with the unhappy lot of being raised as moslem but who subsequently want to move away from it."
"Beinart then goes on to describe a number of examples of Lieberman's "apostacy" that arguably made the Democratic party stronger."
"And it ought to be remembered, that the guilt of this kind of apostacy hath driven some to despair; as in the case of"