The Collaborative International Dictionary of English v.0.48:
Misestimate \Mis*es"ti*mate\, v. t. To estimate erroneously. --J. S. Mill. [1913 Webster]WordNet (r) 3.0 (2006):
misestimate v 1: judge incorrectly; "I had misestimated his determination" [syn: miscalculate, misestimate] 2: calculate incorrectly; "I miscalculated the number of guests at the wedding" [syn: miscalculate, misestimate]