The Collaborative International Dictionary of English v.0.48:
Magnanimously \Mag*nan"i*mous*ly\, adv. In a magnanimous manner; with greatness of mind. [1913 Webster]WordNet (r) 3.0 (2006):
magnanimously adv 1: in a magnanimous manner; "magnanimously, he forgave all those who had harmed him"