Having the nature or function of expiation; serving to atone or make amends.
From expiate with the adjectival suffix -ive, meaning 'tending to' or 'serving to do.' This is another scholarly adjective formation, less common than expiatory but used in formal religious or philosophical contexts.
While 'expiatory' is the standard form, 'expiative' shows up in older theological texts—language evolves, and sometimes older forms fade away, which is why you see this in academic articles about historical theology.
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