Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
* incūsātĭo, ōnis, f. [incuso], a blaming, accusing, accusation: vitiorum, et peccatorum incusatio, aut querela, Cic. de Or. 3, 27, 106; Don. ad Ter. Phorm. 2, 3, 12.