The headword, actually a genitive plural, is presumably extracted from the quotation (though there are numerous earlier instances).
[1] Greek Anthology 6.240.3-4 (Philip: addressed to Artemis). For the Hyperboreans see also upsilon 248. On this epigram, a prayer for the Emperor's recovery from illness, see Gow and Page vol. I (299) and vol. II (331-332). The identity of the king is uncertain, but Gow and Page believe (vol. II, 331) the most likely possibility is Gaius (Caligula, 12-41CE). Indeed, Gaius had been performing many praiseworthy acts when he became seriously ill (October-November 37), and he was still immensely popular (ibid.); cf. Cassius Dio 59.8-9 and Suetonius Gaius 14 (web address 1).