The act of depraving or corrupting; moral corruption or degradation (archaic).
From deprave (to corrupt morally) + '-ation' (abstract noun suffix). Deprave comes from Latin 'depravare' meaning to corrupt or pervert.
Deprevation was a favorite word of Victorian moralists who worried about the 'deprevation of the young'—it captures that old-fashioned concern about moral corruption that rarely comes up in modern English.
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