The headword is a feminine noun in the nominative (and vocative) singular; see LSJ s.v. It occurs in some texts with the variant spelling o)rqogo/h, but this is the authentic version. From Hesiod, Works and Days 568 (web address 1); see the scholia there.
[1] The gloss is the same grammatical form as the headword. Identical glossing -- albeit of o)rqogo/h: see above -- in the Synagoge, Photius' Lexicon (omicron469 Theodoridis), Lexica Segueriana 320.11, Etymologicum Gudianum 433.38, and Hesychius omicron1189; cf. Etymologicum Magnum 631.4 (Kallierges).
[2] This adjective, another epithet of the swallow, is evidently prompted by the quotation given (its only attestation), where it appears in the feminine dative plural. [In her critical apparatus Adler notes that ms A has o)rqo/lalos.]
[3] Greek Anthology 6.247.1 (Philip), the weaver Aesione's dedication to Athena; cf. Gow and Page (vol. I, 312-313); (vol. II, 345); and further extracts from this epigram at alpha 4378, kappa 2515, lambda 371, and tau 39.