The Collaborative International Dictionary of English v.0.48:
Insensibly \In*sen"si*bly\, adv. In a manner not to be felt or perceived; imperceptibly; gradually. [1913 Webster] The hills rise insensibly. --Addison. [1913 Webster]WordNet (r) 3.0 (2006):
insensibly adv 1: in a numb manner; without feeling; "I stared at him numbly" [syn: numbly, insensibly]