What does apostacy mean?
Apostacy — more commonly spelled apostasy — denotes the deliberate abandonment or renunciation of a religious faith, belief system, or guiding principle by someone who once professed it. The term derives from the Greek 'apostasis', meaning a defection or 'standing away', and entered English through Latin in the medieval period. In religious contexts it carries heavy weight: many traditions have historically regarded apostacy as among the gravest offenses, sometimes punishable by excommunication or, in some legal systems still today, by severe civil penalties. Beyond religion, the word is used figuratively to describe a politician deserting a party line or an advocate abandoning a long-cherished cause, usually with an implication of betrayal. It should be distinguished from heresy, which involves holding unorthodox beliefs within a faith rather than leaving the faith altogether. Writers today overwhelmingly favor the standard spelling 'apostasy'.
nounApostacy (more commonly spelled apostasy) is the formal or deliberate abandonment or renunciation of a religious faith, belief, or principle by someone who previously professed it.
- The renunciation or abandonment of a religious faith or belief by a former adherent.
- By extension, the abandonment of a political party, cause, or set of principles one formerly supported.
"After years of doubt, his apostacy from the church of his upbringing shocked the community that had once celebrated him as a devout member."
"The council treated his apostacy as grounds for formal excommunication."
"Political rivals branded her support for the opposing bill an unforgivable apostacy."
The plural is rare in practice, since the word typically describes individual acts; it may appear when comparing multiple historical cases.
"Historians catalogued the great apostacies of the early church alongside later waves of conversion and reversion."
The word traces back to Greek 'apostasis' — literally a 'standing away' — making every apostate, in the original sense, someone who has simply stepped away.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of apostacy
Apostacy comes from the Greek 'apostasia', meaning defection or revolt, formed from 'apistemi' ('to stand away' or 'withdraw'), which combines 'apo-' ('away from') with a verb of standing. The term passed into ecclesiastical Latin as 'apostasia' and entered English via Old French and Latin around the late medieval period, originally referring specifically to renunciation of the Christian faith. The variant spelling 'apostacy' arose through English usage influenced by related forms such as 'apostate'; the standard modern spelling is 'apostasy'. Cognate English derivatives include 'apostate' (one who commits apostacy) and the verb 'apostatize'.
How apostacy is actually used
The spelling 'apostacy' is a recognized variant of the far more common 'apostasy'; most modern dictionaries and style guides prefer 'apostasy'. The word carries a strongly negative connotation in religious contexts, where it has historically been treated as a grave offense. In secular usage it often appears metaphorically for betraying a political cause or principle.
Easily confused with apostacy
Apostasy is the standard spelling of the same word; 'apostacy' is an accepted but less common variant spelling, not a different meaning.
Heresy is holding beliefs contrary to official doctrine while remaining within a faith, whereas apostacy is the outright abandonment of the faith itself.