Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
ab-nūto, āvi, ātum, 1, v. freq. [id.], to deny (by a nod) often, to refuse: quid te adiri (Vahl. adirier; Rib. adiri tam) abnutas, Enn. ap. Cic. de Or. 3, 41, 164 (where Cic. censures the word as less forcible than vetas, prohibes, absterres, and the like): quid mi abnutas? Tibi ego abnuto? Plaut. Capt. 3, 4, 79.