Green’s Dictionary of Slang

1. a commotion, a fight.

1892		‘’Arry in Venice’ in Punch 27 May 88/2: Defending the State, I persoom, and they’re ’aving a fust-class old beano.
1906		E. Dyson Fact’ry ’Ands 219: Er fair ole beano! [...] They’ve dumped Toucher in ther dust-box for immedjit removal.
1917		‘Sapper’ No Man’s Land 111: The ’Un will be strafing [...] and there’ll be the ’ell of a beano going on.
1986		R.G. Barrett Godson 56: [of a bar fight] ‘Bit of a beano that one, what?’.

2. (also beeno) a party, a celebration.

1888		C.T. Jacobi Printers’ Vocab. 7: Beano, a slang abbreviation for ‘beanfeast’, which is, however, usually termed ‘goose’ or wayzgoose by compositors [OED].
1892		‘Coming of Age’ in ‘F. Anstey’ Mr Punch’s Model Music Hall 116: Oh, I am ’aving a beano!
1897		W.S. Maugham Liza of Lambeth (1966) 20: It’ll be a regular beeno.
1900		Sporting Times 21 Apr. 1/2: He took the old Dutch and the kids to the sea / For a beano or national holiday.
1904		Sun. Times (Perth) 3 Apr. 4/5: Burglar Bill [...] entertained several of the talent at a beer beano the same evening, the function taking place in the Wife Beaters’ Arms.
1912		Rollitt & LeBrunn [perf. Marie Lloyd] I’ve never lost my last train yet 🎵 We had a fair old beano on the way.
1915		C.J. Dennis ‘Hitched’ in Songs of a Sentimental Bloke 80: An’ then we ’as a beano up at Mar’s – / A slap-up feed, wiv wine an’ two big geese.
1925		Wodehouse Carry on, Jeeves 70: I had met Bicky for the first time at a species of beano or jamboree.
1930		K.S. Prichard Haxby’s Circus 235: A mob of shearers [...] were having ‘a beano’ at the local pub.
1941		K. Tennant Battlers 100: [He] invited the busker to ‘a bit of a beano’ which the dark people were holding that night.
1947		H. Brush 11 April diary in Garfield Our Hidden Lives (2004) 379: A gardener is an angry man / When he has done dug and raked and hoed [...] And then the neighbour’s cats come round / And hold a ‘beano’ on his ground.
1953		Western Mail (Perth) 26 Mar. 24/3: If prices came down [...] ordinary families could also have a mild sea-food beano.
1954		Wodehouse Jeeves and the Feudal Spirit 67: You have some beano in prospect?
1968		T. Wolfe Electric Kool-Aid Acid Test (1969) 216: There was no way in the world anybody could have made the Vietnam Day Committee realize how their whole beano looked to Kesey and the Pranksters.
1987		T. Wolfe Bonfire of the Vanities 4: They’re waiting for the beano, for the rock fight.
1999		Indep. on Sun. 5 Sept. 26: We’re off to the Ivy for a slap-up beano.
2012		Spitalfields Life 18 Jan. 🌐 In those days [i.e. 1960s], people didn’t go on holidays [...] they had what they called ‘beanos,’ pub and work excursions going to Margate or Southend.