Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
sŏnax, ācis, adj. [sono], sounding, noisy (poet. and in post-Aug. prose): concha, App. M. 4, p. 157, 3: dentium attritus, id. ib. 8, p. 202, 30.