The Collaborative International Dictionary of English v.0.48:
Impertinently \Im*per"ti*nent*ly\, adv. In an impertinent manner. "Not to betray myself impertinently." --B. Jonson. [1913 Webster]WordNet (r) 3.0 (2006):
impertinently adv 1: in an impudent or impertinent manner; "a lean, swarthy fellow was peering through the window, grinning impudently" [syn: impertinently, saucily, pertly, freshly, impudently]