apostate

An apostate is someone who has deserted his cause.

The word apostate originally comes from a Greek word that meant "runaway slave." Now, apostate has a religious or political tone to it, so someone might call you "a political apostate" if you ran for office as a Republican during one election and then ran as a Democrat in the following election.

Definitions of apostate
1

adj not faithful to religion or party or cause

Synonyms:
unfaithful
not true to duty or obligation or promises

n a disloyal person who betrays or deserts his cause or religion or political party or friend etc.

Synonyms:
deserter, ratter, recreant, renegade, turncoat
Type of:
quitter
a person who gives up too easily

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