One who expiates; a person who makes atonement or amends for wrongdoing.
From Latin expiator, agent noun from expiare (to expiate). The form comes directly from Latin with the -or agent suffix, used in English to name someone who performs an action.
In religious texts, Christ is sometimes called the ultimate 'expiator'—the one whose sacrifice atones for all humanity, which is why this term, though rare, carries tremendous theological weight.
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