nan boy, n. — Green’s Dictionary of Slang

nan boy n.

also nan

[the girl’s name Nan, then synon. with colloq. nan, a serving-maid]

an effeminate or homosexual male.

1671		‘L.B.’ New Academy of Complements 201: The Gittarn, the Lute, / The Pipe, and the Flute, / Are the new Alamode for the Nan boys.
1693		‘Jenny Cromwells Complaint against Sodomy’ Harleian Mss. 73I5.226: Scarsdale [...] skulks about the Alleys And is content with Bettys, Nans and Mollys.