Green’s Dictionary of Slang

1. thieves’ jargon.

c.1566		Harman Caveat for Common Cursetours in Viles & Furnivall (1907) 23: As far as I can learne or understand by the examination of a number of them their language – which they terme peddelars Frenche or Canting – began but within these xxx yeeres, or lytle above; and that the first inventer therof was hanged, all save the head; for that is the fynall end of them all, or els to dye of some filthy and horyble diseases: but much harme is don in the meane space by their continuance, as some x., xii., and xvi. yeares before they be consumed, and the number of them doth dayly renew.
1577		W. Harrison Description of Britain in Ribton-Turner (1887) 466: Moreover in counterfeiting the Egyptian rogues they have devised a language among themselves, which they name Canting but other pedler’s French a speach compact thirtie yeares since of English, and a great number of od words of their owne devising, without all order or reason: and yet such is it as none but themselves are able to understand.
1608		Dekker Lanthorne and Candle-Light Ch. 1: As these people are strange both in names and in their condition, so doe they speake a Language (proper only to themselues) called Canting.
1615		T. Overbury New and Choise Characters n.p.: [A Canting Rogue] The Northern speech differs from the South, Welch from the Cornish; but Canting is generall, nor euer could be altered by Conquest of the Saxon, Dane, or Norman.
1626		Jonson Staple of News IV i: Is not this old canting? do you understand him?
1641		R. Brome Jovial Crew II i: I understand their canting.
a.1661		‘The Cock-Crowing at the Approach of a Free-Parliament’ Rump Poems and Songs (1662) II 173: We’ll preach and pray ’thout canting, / In a Language Heaven knows better / Than ah Lord repeating.
1674		Head Canting Academy (2nd edn) 2: There is no profest Rogue whatsoever [...] but must be well vers’d in Canting.
1688		T. Shadwell Squire of Alsatia I i: He [...] spoke a particular language which such rogues have made to themselves, called canting, as beggars, gipsies, thieves, and gaolbirds do.
c.1698		B.E. Dict. Canting Crew n.p.: Canting, the Cypher or Mysterious Language, of Rogues, Gypsies, Beggers, Thieves, etc.
1706		Farquhar Recruiting Officer III i: I was born a gipsy, and bred among that crew [...] There I learned canting and lying.
1707		J. Shirley Triumph of Wit 177: Since Wheedling and Canting may be justly termed Brethren, I don’t think it any ways amiss to join them together in this Third Part of my Academy [...] This word canting seemes to bee derived from the latine verbe (canto) which signifies in English, to sing, or to make a sound with words, thats to say to speake. And very aptly may canting take his derivation a cantando, from singing, because amongst these beggerly consorts that can play upon no better instruments, the language of canting is a kinde of musicke, and he that in such assemblies can cant best, is counted the best Musitian.
1737, 1759, 1760, 1776		Bailey Universal Etym. Eng. Dict.
1785, 1788, 1796		Grose Classical Dict. of the Vulgar Tongue n.p.: Canting [...] a kind of gibberish used by thieves and gypsies, called likewise pedlar’s French, the slang, &c. &c.
a.1790		H.T. Potter New Dict. Cant (1795).
1811		Lex. Balatronicum.
1821		Flash Dict.
1824		(con. 17C) W. Scott Redgauntlet (1827) 63: ‘What trade be’s that, man?’ said he [...] ‘Canting and lying,’ – said Willie, which produced a thundering laugh.
1835		G. Kent Modern Flash Dict.
1848		Flash Dict. in Sinks of London Laid Open.

2. attrib. use of sense 1.

1620		J. Melton Astrologaster 15: The Gypsies Canting Tongue.
1630		J. Taylor ‘Taylors Revenge’ in Works (1869) II 146: Instructing thee in the braue Canting tong / And how in Pedlers French to sing a song.
1728		J. Dalton Narrative of Street-Robberies 60: A Key to the Canting Language.
1734		C. Johnson Hist. of Highwaymen &c 105: Because thou art a Novice in begging, and understand not the Mysteries of the Canting language.
1742		Johnson Highwayman and Pyrates 57: All the canting language (which comprehends a parcel of invented words, such as thieves very well know, and by which they can distinguish one another from the other classes of mankind) [F&H].
1856		C. Reade It Is Never Too Late to Mend II 241: Mr. Miles flung canting rogue and half-a-dozen oaths.