To TWIG,
to disingage, to sunder, to snap, to break off; as, To twig the Darbies; To knock off the Irons.
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Entry taken from 1736 Canting Dictionary, by Nathan Bailey.
To Twig in the 1811 Vulgar Tongue
Also see examples in Canting Songs and Slang Rhymes collected by John S. Farmer (1896).