Green’s Dictionary of Slang

1. a dissolute and violent young man, usu. an aristocratic rowdy, who caroused through the streets of London beating up passers-by, attacking watchmen, smashing windows etc; occas. of a woman, a prostitute; thus mohacking/mohawking n., behaving in this way.

1712		Lady Strafford Wentworth Papers diary 14 Mar. in Massingham London Anthology 106: I am very much frightened with the fyer, but much more with a gang of Devils that call themselves Mohocks; they put an old woman into a hogshead, and rooled her down a hill, they cut some nosis, others hands.
1718		M. Prior Alma in Works (1959) I 506: From Milk-sop He starts up Mohack: [...] So thro’ the Street at Midnight scow’rs: Breaks Watch-men’s Heads, and Chair-men’s Glasses.
1719		in D’Urfey Pills to Purge Melancholy II 347: Where Fops and Strumpets, and Mohocks might be, / And rakehells, just like Pinktheman And Lee.
1723		C. Walker Authentick Memoirs of Sally Salisbury 110: The first question our Female-Mohock put to the He One, were: Do you think the Pimp will come down? Will he bleed plentifully? Is he flush of gold?
1723		advert in Proceedings Old Bailey 16 Jan. 8/2: A complete Collection of remarkable Trials [...] for the Crimes following: Murders, Highway-Robbing, Piracy, House-breaking, Foot padding, Rapes, Sodomy, Polygamy, Fortune-stealing, Trespassing, Shop-lifting, Callicoe-tearing, Mohocking, High-Treason.
1755		Gent.’s Mag. xxv 65: The mohocks and Hell-Fire-Club, the heroes of the last generation [F&H].
1767		Stamford Mercury 3 Dec. 1/1: What prowess modern Bucks display, / Above the sneaking feats we’re told / Of reptile Bloods, in times of old; / When Scow’rers and Mohocks laid claim / To all the flattery of the flame.
1785		Grose Classical Dict. of the Vulgar Tongue n.p.: Chalkers, men of wit in Ireland, who in the night amuse themselves, with cutting inoffensive passengers across the face with a knife. They are somewhat like those facetious gentlemen, some time ago known in England, by the title of sweaters and mohocks.
1786		F. Pilon He Would be a Soldier V i: We’ll drive round [...] and take this young mohawk by surprise; the moment you get possession of him, banish him to Wales.
1818		Times 28 Oct. 3/2: The bucks among our ancestors were designated by the name of Mohawks, and wherever they went they were avoided like American savages.
1825		J. Neal Brother Jonathan I 227: Does he ever go out ‘a mohawking’?
1839		(con. 1715) W.H. Ainsworth Jack Sheppard (1917) 116: So, the Mohocks have been at work, I perceive.
1850		E.V. Kenealy Goethe: a New Pantomime in Poetical Works 2 (1878) 337: Codger, Spooney, Fogie, Ass, / Vile Mohock, Screw, Gaby, Gudgeon.
1859		G.A. Sala (ref. to early 18C) Twice Round the Clock 209: The ‘Mohocks,’ ‘Scourers,’ and ‘Sweaters’ of Queen Anne’s time.
1863		(ref. to mid-18C) Shields Dly Gaz. 17 Sept. 3/4: The deeds which delighted the buckskin breeches and cocked hats of our Maccaronis and Mohawks in the days of the second George.
1875		Sporting Gaz. (London) 27 Nov. 5/2: Rows with the police are voted ‘bad form’ nowadays, even among those licensed Mohawks, medical students.
1883		‘’Arry on His Critics and Champions’ in Punch 14 Apr. 180/1: Can’t say as to Mohocks and sech like, but undergrads, Mashers or me, / We all likes a turn at the bellows when properly out on the spree.
1892		H. Garland Spoil of Office 194: We old mohawks are a damage to any man’s campaign.
1894		(ref. to c.1710) G.A. Sala Things I Have Seen II 71: The Mohocks of Queen Anne’s time.
1968		G. Legman Rationale of the Dirty Joke (1972) I 180: The sword-bearing, aristocratic Mohocks.

2. (UK und.) a short knife used as a burglar’s tool.

1732		Proc. Old Bailey 19 Apr. 103/2: This Instrument was found in his Pocket, one part of it is a Saw that will cut an Iron-bar, another is a Sharp Knife, and a third a Tool that they call a Mobock [sic].
1750		Proc. Old Bailey 25 Apr. 67/2: I took two guineas out of Savage's mouth; he had got them in a chew of Tobacco in his mouth, and I hooked them out with a mohock knife.