Green’s Dictionary of Slang

1. dubious, underhand or crooked practices; also attrib.

1882		Cincinnati Enquirer 13 June 4/2: There are intimations by cable that Arabi Pasha has been practicing what would be called among the ‘boys’ in America ’monkey business;’ that he has been pretending to be thrashed when he wasn’t.
1891		O.P. Reid Twenty Good Stories 101: [advert] All the new card tricks and sleight-of-hand monkey-doodle business. Price, 25 cents.
1893		Neihart Herald (MT) 9 Dec. 1/3: Fortunately there is no monkey-doodle business going on in Neihart.
1896		J.F. Lillard Poker Stories 52: Devill comes back and begins his monkey business again.
1898		Wichita Dly Eagle (KS) 23 Oct. 12/2: It is a shame for this nation to allow any monkey-doodles on Bianco’s part.
1904		Sydney Sportsman (Surry Hills, NSW) 13 July 3/5: [N]o ‘monkey business’ will be tolerated.
1905		H. Green Actors’ Boarding House (1906) 263: If you’re four-flushin’ say so, ’cause I won’t stand no monkey business.
1913		Rock Is. Argus (IL) 30 Oct. 12/7: Officer Charles Ginnane put a stop to the monkey doodles.
1914		S. Lewis Our Mr Wrenn (1936) 21: I let him see from the way I looked at him that I wasn’t going to stand for no more monkey business.
1925		Dos Passos Manhattan Transfer 328: If you ever hear a man talking about his duty as a citizen [...] He’s up to some kind of monkey business nine times out of ten.
1925		D. Hammett ‘Corkscrew’ Story Omnibus (1966) 233: You may be a curly wolf with your rod [...] but if you try any of your monkey’s business on me, I’ll turn you over my knee.
1932		R. Fisher Conjure-Man Dies 49: The only business what was flourishin’ was monkey-business [...] Cheatin, — backbitin, and all like that.
1941		Eve. Teleg. (Dundee) 10 Mar. 7/2: [advert] There’s no Monkey Business about the value in fine quality Groceries [...] offered by Johnston’s Stores.
1947		B. Schulberg Harder They Fall (1971) 144: No monkey business on the road.
1951		M. Spillane Long Wait (1954) 48: Vera and Johnny worked together until the monkey business in the bank came out.
1960		B. Kops Dream of Peter Mann Act I: jason: I said I have business to discuss with you later. sonia: As long as it’s not monkey business.
1980		M. Bail Homesickness (1999) 338: And no monkey business, please.
1996		S. Bell If... 13 June in If Files (1997) 86: Any monkey business out o’ ye, and, by the bloody red buttock of O’Neil, we’ll be blowing ye away like vermin.
2001		David Byrne ‘Neighborhood’ 🎵 We’ve got peace, love, and monkey business.
2011		J.J. Connolly Viva La Madness 238: Jesus was doing his monkey business [...] shifting tackle, making money but spinning out of control.

2. foolish activities, ‘messing around’.

1883		G.W. Peck Peck’s Bad Boy and His Pa (1887) 91: Pa said [...] that there musn’t be no monkey business going on.
1895		Mirror of Life 3 Aug. 10/2: ‘I wasn’t going to put up with any such monkey business being led around like a dime museum freak.
1902		T.A. Dorgan in Zwilling TAD Lex. (1993) 58: Johnny Wise Starts A Little ‘Monkey Doodles’ At The Seaside.
1911		G.R. Sims Off the Track in London 104: It is the predominace of the boy and girl element that has given it a reputation for the ‘monkey’ business.
1914		R. Lardner You Know Me Al (1984) 124: You can cut out the monkey business and drink water when you are thirsty or else you can go up to Milwaukee and drownd yourself in one of them brewrys.
1917		C. Sherwood diary 22 Sept. 🌐 Too much show and monkey business without learning anything.
1922		Joyce Ulysses 115: Monkeydoodle the whole thing.
1927		(con. 1900s) S. Lewis Elmer Gantry 159: Now I don’t want any monkey business about this. A preacher must walk circumspectly.
1928		Sat. Eve. Post 12 May 41/2: They ought not to go abroad with such monkey-doodle business [DA].
1934		E.C. Segar ‘Thimble Theatre’ [comic strip] I wants you lubbers to lay off the monkey bizniss.
1945		A. Kober Parm Me 63: Nothing but kissing here and kissing there. Feh! This monkey business I don’t like.
1959		G. Slatter Gun in My Hand 209: Well, no monkey business, that’s all.
1966		M. Rumaker Exit 3 and Other Stories 27: I’m tired of the whole monkey business.
1975		D. Nobbs Fall and Rise of Reginald Perrin (1976) 158: No more monkey business, Hump!
2011		‘Jack Tunney’ Split Decision [ebook] You work ’em up, get ’em good and thirsty. But no more monkey business.

3. a euph. for sexual intercourse.

1934		‘J.M. Hall’ Anecdota Americana II 21: I wants to be paid if yo all goin’ to have monkey business wit me tonight.
1943		W.R. Burnett Nobody Lives for Ever 84: ‘You better make this take without any monkey business or I’m going to be very, very annoyed.’ ‘She’s a nice woman. No nonsense’.
1960		(con. 1930s) R. Barber Night They Raided Minsky’s (1968) 255: I don’t wanna hear the old geezers, I don’t wanna hear anybody who’s over the hill and no good for any more monkey-doodle — if you know what I mean!