Synonyms for Affirmative (same or very similar meaning)
WordNet sense 1 (in favor of (an action or proposal etc.)):
pro
WordNet sense 2 (expecting the best):
optimistic
WordNet sense 3 (characterized by or displaying affirmation or acceptance or certainty etc.):
positive
WordNet sense 4 (supporting a policy or attitude etc):
favoring
WordNet sense 5 (affirming or giving assent):
affirmatory
From the ODE community, based on WordNet
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