Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
Būca, ae, f., a town in Samnium, Mel. 2, 4, 6; Plin. 3, 12, 17, § 106.
Hence, Bū-cāni, ōrum, m., the inhabitants of Buca, Inscr. Murat. 1032, 4.