Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
† bōx, bōcis, m., = βώξ, βόαξ, a sea-fish, otherwise unknown, Plin. 32, 11, 53, § 145. In Paul. ex Fest. p. 30, 6 Müll. (Jan. boca), bocas: bocas = genus piscis a boando id est vocem emittendo appellatur; cf. lsid. Orig. 12, 6, 9.