Green’s Dictionary of Slang

tradesman n.

a thief.

1754		Scoundrel’s Dict. 30: Good People give Ear, while a story I tell / Of twenty black Tradesmen who were brought up in Hell.
1796		Grose Classical Dict. of the Vulgar Tongue (3rd edn) n.p.: Tradesmen. Thieves. Clever tradesmen; good thieves.
1811		Lex. Balatronicum [as cit. 1796].
1823		Egan Grose’s Classical Dict. of the Vulgar Tongue.
1859		Matsell Vocabulum.
1873		Sl. Dict. 328: Tradesman one who thoroughly understands his business, whatever it may be. No better compliment can be passed on an individual, whether his profession be housebreaking, prizefighting, or that of a handicraftsman, that the significant, ‘He’s a regular tradesman.’.