Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
dēmūtātĭo, ōnis, f. [demuto], a changing, change (very rare, and critically certain only in late Lat.): demutatio morum, Cic. Rep. 2, 4, 7 dub.: carnis, Tert. Res. carn. 55; id. adv. Marc. 4, 1; 5, 10 fin.