Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
mŏdĭfĭcātĭo, ōnis, f. [modificor], a measuring, measure (post-Aug.): versuum lex ac modificatio, Sen. Ep. 88, 3: verborum, Gell. 10, 3, 15; cf. Paul. ex Fest. p. 160, 10 Müll.