Green’s Dictionary of Slang

gyvel n.

also gavel, gyvle
[SE gyve, a shackle, a fetter]

(Scot.) the vagina.

[Scot] Burns ‘The Court of Equity’ in Merry Muses of Caledonia (1965) 212: Tho’ it’s weel-kend that, at her gyvle, / Ye hae gien mony a kytch an’ kyvle.
[Scot]Burns ‘Come rede me, dame’ in Merry Muses (1964) 61: Come lowse and lug your battering ram, And thrash him at my gyvel.
[UK] ‘The Court of Equity’ in Farmer Merry Songs and Ballads (1897) IV 284: Ye never herried Maggy’s nest; / Tho’ it’s weel-kenn’d that at her gyvel / Ye’ve done what Time will soon unravel.
[Scot] Burns ‘Eppie McNab’ in Merry Muses of Caledonia (1965) 127: My blessings upo’ thee, Jock Rob, Jock Rob, / For in my gavel ye drive sic a dool.
[UK]Farmer & Henley Sl. and Its Analogues.