Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
dispertītĭo, ōnis, f. [dispertio], a division, destruction: urbis, Cic. Phil. 3, 12, 30 fin. (where disperditio is a false reading, but v. dispersio); Tert. adv. Herm. 31.