The headword is a masculine (and feminine) adjective in the nominative singular; see LSJ s.v. In the first quotation given here it appears in the accusative singular; in the second, in the dative singular.
[1] Identically glossed in the Synagoge, Photius' Lexicon (omicron684 Theodoridis), and Lexica Segueriana 322.24; cf. Hesychius omicron1859 and ps.-Zonaras 1479 s.v. ou)=ros, an alternative spelling. Adler also cites the Lexicon de Spiritu, L.C. Valckenaer, ed.
[2] Polybius 1.44.3 (web address 1). It describes Hannibal's (OCD(4) s.v. and alpha 2452) audacious running of the Roman blockade (250 BCE) around the harbor at Lilybaeum (the present-day Italian city of Marsala, on Sicily's far western coast; Barrington Atlas map 47 grid A3) during the First Punic War (264-241); see Walbank, pp. 104-9.
[3] Sophocles, Ajax 889 (web address 2), with comment from the scholia there: the chorus of Salaminian sailors laments their lack of such access to Ajax, who has already fallen on his sword.