Green’s Dictionary of Slang

mingo v.1

[obs. SE meng, to have sexual intercourse]

to have sexual intercourse.

[UK] ‘A cup of old Stingo’ in Ebsworth Merry Drollery Compleat (1875) 141: ’Twill make a Parson not to flinch, / Though he seem wondrous holy, / But for to kiss a pretty Wench, / And think it is no follie; / ’Twill make him learn to decline / The Verb that’s called Mingo, / ’Twill make his Nose like Copper shine, / If his head be lin’d with stingo.