Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
dēstructor, ōris, m. [destruo], one who pulls down, a destroyer: rerum, opp. aedificator, Tert. Apol. 46: Trojae, Cass. Var. 14, 15; Hier. Ep. 112, 10 fin.