Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
impūrĭtĭa (inp-), ae, f. [impurus], uncleanness, vileness, impurity, = impuritas (anteand post-class.; very rare): trecentis versibus Tuas impuritias transloqui nemo potest, Plaut. Pers. 3, 3, 7: deliquentium, Mos. et Rom. Leg. Coll. 6, 4, 3.