Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
† archōn, ōntis, m., = ἄρχων (a ruler), the highest magistrate at Athens after the abrogation of royal authority, an archon, * Cic. Fat. 9, 19; cf. Vell. 1, 2 and 8.