Green’s Dictionary of Slang

1. heavily.

1590		Sidney Arcadia III (1912) 433: He began to deal some blowes, and his arme (being used to flaile in his youth) laid them on so thick, that Clinias now began with lamentable eies to see his owne blood.
a.1625		Beaumont & Fletcher Love’s Cure I i: All arm’d, advanc’d within shot of their Walls, From whence the Musquetiers plaid thick upon him.
1721		Cibber Refusal 16: I rais’d my Fortune, Sir, as Milo lifted the Bull, by sticking to it every day [...] I sous’d them with Premiums, Child, and laid them on thick when the Stock was low.
1822		Westmorland Gaz. 27 Apr. 4/5: Coachee [...] you needn’t be afeard of laying it [i.e. a fare] on pretty thick.
1841		D. Boucicault London Assurance in London Assurance and other Victorian Comedies (2001) Act V: I am always thick on the winning horse.
1842		Whip & Satirist of NY & Brooklyn (NY) 12 Mar. n.p.: Don’t be quite so coarse. We think you put it on a little too thick.
1895		J. Greenwood Behind A Bus 151: It was a dead certainty, as I told you, and I went in for it thick.

2. intensely, severely.

1839		W.A. Miles Poverty, Mendicity and Crime; Report 108: Bill, the parson has been laying it into you pretty thick, I think.
1840		E. Howard Jack Ashore III 273: It does my poor broken heart good to hear ye cuss that sodger – go it again, my daffydown-dilly, and lay it on thick.
1887		W.T. Call Josh Hayseed in N.Y. 117: You’re pilin’ it on too thick.
1895		Derby Mercury 9 Jan. 8/3: Costy, I've got it a bit thick, suppose I give him a bit of a chivy and see how he likes it.
1900		Marvel 15 May 3: He was talking pretty thick of what he would do if he met one of them.
1905		Marvel III:58 19: You know how the cops are thick on our track.
1913		A. Lunn Harrovians 23: He had an uncomfortable feeling that Mr. Pycroft was piling it on rather thick.
1916		T.A. Dorgan in Zwilling TAD Lex. (1993) 34: (IS: Listening to the boys salve the boss about the old tin cup he won on the links Saturday) Oh — boy They all like it — They all eat it up — I like it meself but not too thick.
1922		Joyce Ulysses 79: Still, having eunuchs in their choir that was coming it a bit thick.
1943		Kerouac letter in Charters I (1995) 62: This, of course, is pouring it on thick, but I wanted to see his reaction.
1999		‘Master Pimp’ Pimp’s Rap 6: I had spotted a dark brown skin sexy sister who was putting it on thick.
2010		(con. 1973) C. Stella Johnny Porno 188: They put the hammer to her. ‘Turn informant or get used to munching muff the next dozen years’ [...] They laid it on thick.

3. densely.

1932

(con. 1910s) J.T. Farrell Young Lonigan in Studs Lonigan (1936) 67: He couldn’t spread the bull on thick.

4. intimately.

1893		R.W. Emerson Signor Lippo 91: She looked for all the world like a gippo, and she knew all the cant, and used to palarie thick to the slaveys.
1901		Boy’s Own Paper 25 May 531: You were in mighty thick with Cockle.
1973		G.V. Higgins Digger’s Game (1981) 13: He’s in pretty thick with Bishop Hurley there.