Tending to affirm or confirm; serving to strengthen or add force to something (rare or obsolete).
From Latin 'affirmare' (to assent to, confirm), combining 'ad-' (to) and 'firmare' (to make firm). The '-ative' suffix indicates a tendency toward the root meaning.
This is one of those rare historical words that almost nobody uses anymore—'afformative' meant something that adds force or confirmation to an argument, but 'affirmative' eventually muscled it out of the language.
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