The Collaborative International Dictionary of English v.0.48:
hesitater \hesitater\ n. one who hesitates. Syn: waverer, vacillator, hesitator. [WordNet 1.5]WordNet (r) 3.0 (2006):
hesitater n 1: one who hesitates (usually out of fear) [syn: waverer, vacillator, hesitator, hesitater]