Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
intĕremptĭo (-emt-), ōnis, f. [interimo], destruction, slaughter, Tert. adv. Prax. 27; Porc. Lat. Decl. in Cat. 10 (but a false reading for internecione, Cic. de Imp. Pomp. 11, 30).