The Collaborative International Dictionary of English v.0.48:
Affirmatory \Af*firm"a*to*ry\, a. Giving affirmation; assertive; affirmative. --Massey. [1913 Webster]WordNet (r) 3.0 (2006):
affirmatory adj 1: affirming or giving assent; "an affirmative decision"; "affirmative votes" [syn: affirmative, affirmatory] [ant: negative]