The Collaborative International Dictionary of English v.0.48:
Extemporarily \Ex*tem"po*ra*ri*ly\, adv. Extemporaneously. [1913 Webster]WordNet (r) 3.0 (2006):
extemporarily adv 1: without prior preparation; "he spoke extemporaneously" [syn: extemporaneously, extemporarily, extempore]