[Meaning a] eunuch.[1]
In the Epigrams: "Gallus the long-haired, the lately-cut, a Lydian from Tmolus who once shrieked long for dancers."[2]
Also [sc. attested is the plural] Galloi ["Galli"], eunuchs. "Gnaeus [Manlius], the Romans' consul, crossed and bridged the Sangarius river, which is in a hollow and altogether difficult to cross; and there came to him as he was encamped at the river Galli from Attis and Battacus, priests of the Mother of the gods from Pessinus, who had in addition to her image [other] figurines, and who said the goddess foretold his victory and power; Gnaeus received them benevolently."[3]
And elsewhere: "he sent out youths whom he had prepared as Galli -- with pipers, in women's robes, and having drums and figurines -- against those besieging the territory."[4]
"Galli come from men, but men do not come about from Galli."[5]