bobbin jo, n. — Green’s Dictionary of Slang

bobbin jo n.

also Bobbing Joan

[the old dance ‘Bobbing Joan’; Williams suggests that Bobbing Joan might also have been generic for a prostitute and cites a similar use of Bobbing Bess in 1654]

sexual intercourse; often as dance bobbin jo.

[a.1651		Rawlinson [ballad title] Bobbin lo Or, The Longing-Lass Satisfied at Last’].
1654		Mercurius Fumigosus 21 18–25 Oct. 183: After one lesson of Bobb-in Joo.
1660		Wandring Whore II 3: [They] cure the Priapismus, Satyriasis, and Standing-Ague infallibly, with an Universal Medicine, dancing BBobb in-jo, stark naked into the bargain.
a.1871		‘Old Marquis’ in C. Hindley Curiosities of Street Lit. (1871) 131: He cuddled her so sweet, / The damsel he did flatter, / Singing I for Bobbing Joan, / And she for stoney batter.