Green’s Dictionary of Slang

1. trickery, skulduggery, machination, intrigue, teasing, ‘kidding’, nonsense; (usu. pl.) a plot, a trick, a prank, an exhibition of high spirits, a carry-on; also as v, to indulge in such behaviour.

1855		Town Talk (S.F.) 25 Apr. 1: Are you quite sure? No shenanigan?
1858		Leics. Mercury 19 June 2/6: A little ‘shenanigan’ was perpetrated for the benefit of those behind the curtain.
1865		M. MacFie Vancouver Island and British Columbia 416: The slang in vogue in the mining regions is imported mainly from California, and is often as expressive as it is original. [...] Deceit in business is ‘shananigan.’.
1871		L.H. Bagg Four Years at Yale 47: Shenannigan, chaff, foolery, nonsense; especially when advanced to cover some scheme or little game.
1872		Schele De Vere Americanisms 631: Shenannigan, probably a purely fictitious word (though a Dutch origin has been claimed for it), frequently heard in the South and West, and denoting groundless bragging for the purpose of getting the better of another. ‘Shenannigan means any kind of chaff, foolery, nonsense, advanced to cover some little scheme or game.’.
1879		Eve. Chronicle (Virginia City) 10 June in M. Lewis Mining Frontier (1967) 203: It was the lowest down shennanigen that ever was played on two honest men.
1888		Derby Mercury 8 Feb. 6/2: Look hyar, old man [...] you’re trying Shenanigan on us.
1889		Era (London) 21 Sept. 15/1: [as personnification] He understood there was some discomfort at theincreased prices; but [...] they could not blame him if, on the night of his benefit, he, like a good ‘shenanigan’ got all he could.
1890		‘’Arry on the Sincerest Form of Flattery’ Punch 20 Sept. 144/2: Never mind their shenanigan, Charlie.
1897		Outing (N.Y.) XXIX 483/1: He is with a man who is firmly kind, but who will stand no shinanigan [DA].
1901		J. London ‘Local Color’ Complete Short Stories (1993) I 693: Come now! [...] No shenanagin! The Cowbell must have you. It hungers for you.
c.1905		J. Furphy Rigby’s Romance (1921) Ch. vii: 🌐 No (adj.) shinnanigan about the Bible [...] Straightest book ever wrote.
1909		L.W. Payne Jr ‘Word-List From East Alabama’ in DN III:v 368: shenannigin, n. Fooling: often with around. ‘Quit your shenannigin’.
1913		J. London Valley of the Moon (1914) 357: I’ve put up with all your shenanigan I’m goin’ to.
1925		(con. 1899) H.P. Bailey Shanghaied Out of Frisco 105: ‘I jest made a straight coat-tail up the lane to her heart,’ gurgled the ecstatic Ben. ‘No shennanikin.’.
1926		S. O’Casey Plough and the Stars Act II: I’ve something else to do besides shinannickin’ afther Judies!
1929		L. Thomas Woodfill of the Regulars 168: Holy mither of all the saints [...] what kind of shenanigans is that?
1935		J. Conroy World to Win 248: I don’t want no more shenanigans.
1938		H. Asbury Sucker’s Progress 205: Thimble-Riggers displayed their shenanigans on the steamboats.
1947		C.J. Lovell ‘The Background of Mark Twain’s Vocab.’ in AS XXII:2 88: Unquestionably, he gave literary currency to many such well known terms as to pass the buck, high-muck-a-muck, shenanigan, land-office business, Mick, and as easy as rolling off a log.
1949		H. Miller Sexus (1969) 271: No shenanigans now, as in the old messenger bureau.
1952		Lait & Mortimer USA Confidential 185: The following is a rundown on how surface shenanigans shape up in Denver.
1955		T. Williams Cat on a Hot Tin Roof Act III: If there’s any peculiar shenanigans going on around here behind my back, well, I’m no corporation lawyer for nothing.
1961		C. Himes Pinktoes (1989) 156: He took her statement to mean [...] that some shenanigans were going on.
1969		N. Cohn Awopbop. (1970) 53: Most of the shenanigans took place in Philadelphia.
1978		R. Price Ladies’ Man (1985) 237: All of us woofing, groaning, laughing and barking at the shenanigans on the screen.
1983		S. King Christine 59: He was pretty sure that Will Darnell might be up to his ears in other shenanigans; anything from truck hijackings to fake antiques.
1987		(con. 1930s) L. Redmond Emerald Square 144: He’s too bloody freemakin’. I soon cut him off the day he tried his oul’ shinanickin’ with me! I never deal there now.
1989		S. Armitage ‘Ivory’ in Zoom 74: No more cuffuffle / or shenanigans.
1990		(con. early 1950s) J. Ellroy L.A. Confidential 59: The shenanigans perpetrated by the men outside have made the Los Angeles Police Department a laughingstock.
1999		N. Cohn Yes We have No 215: The grandiose town hall is known locally as Fawlty Towers, and its shenanigans are never-ending.
2000		Guardian Guide 8–14 Jan. 52: More juicy undercover shenanigans in a [...] Geordie episode of The Bill.
2011		J.J. Connolly Viva La Madness 12: I was content [...] not [to] get mixed up in any shenanigans.
2011		D.R. Pollock Devil All the Time 41: It seemed to him as if every pervert in southern Ohio was located in Meade. Lately, the newspaper was filled with their sick shenanigans.

2. attrib. use of sense 1, boisterous.

1953

S. Bellow Augie March (1996) 229: Simon and Charlotte [...] laughing and in shenanigan embraces with paper caps and streamers.