Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
exsē̆crābĭlĭtas (execr-), ātis, f. [exsecror], execrableness, abominableness (post class.): vitia pariunt exsecrabilitatem, App. Dogm. Plat. 2, p. 21.