Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
Orchĭus, a, m. and f., the name of a Roman gens.
So, C. Orchius, a tribune of the people, 572 A.U.C., by whom the Lex Orchia was proposed, Macr. S. 3, 17, 2; Schol. Bob. ad Cic. Sest. p. 310, 32 Bait.