Green’s Dictionary of Slang

manchester n.

[? Scot. mang, talk and/or f. Rom. mag, to beg]

(UK Und.) the tongue.

[Aus]Vaux Vocab. of the Flash Lang.
[UK]Egan Grose’s Classical Dict. of the Vulgar Tongue.
[UK]H. Smith Gale Middleton 1 152: I warrant his manchester will never let fall another whid.