The definition of an apostasy is the act of leaving behind, or straying from, your religious or political beliefs or your principles.
(noun)An example of apostasy is when someone decides to become atheist.
See apostasy in Webster's New World College Dictionary
noun pl. apostasies
Origin: ME apostasie < LL(Ec) apostasia < Gr apo-, away + stasis, a standing: see stasis
See apostasy in American Heritage Dictionary 4
noun pl. a·pos·ta·sies
Origin:
Origin: Middle English apostasie
Origin: , from Old French
Origin: , from Late Latin apostasia, defection
Origin: , from Late Greek apostasiā
Origin: , from Greek apostasis, revolt
Origin: , from aphistanai, aposta-, to revolt
Origin: : apo-, apo-
Origin: + histanai, to stand, place; see stā- in Indo-European roots
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