Lewis & Short

Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.

Ărĭāna, ae, f., a general name of the eastern provinces of the great Persian kingdom, now Afghanistan, Mel. 1, 2, 4; Plin. 6, 23, 25.
Hence, Ărĭānus, a, um, adj., of or pertaining to Ariana: regio, Plin. 6, 23, 25, § 93.Ărĭāni, ōrum, m., the inhabitants of Ariana, Plin. 6, 25, 29, § 116.