Green’s Dictionary of Slang

brannigan n.

also branigan
[? proper name, but more likely f. stereotype of the fighting Irish drunk; note Jim ‘Lugs’ Brannigan, a popular Dublin policeman renowned for dealing with street fights in a fair manner in 1920s–30s]
(US)

1. a drunken spree; often as on a brannigan; also as adj., drunk.

[US]W. Norr Stories of Chinatown 31: What in Pell street parlance is termed a ‘brannigan,’ a condition produced by two gallons of mixed ale to one quart of whiskey.
[US]Salt Lake City (UT) 30 Mar. 4/5: He has [...] a skate on [...] a brannigan on.
[US]Ade Knocking the Neighbors 48–9: The Reveler finds his bright crimson Brannigan slowly dissolving itself into a Bust Head.
[US]Ade Hand-made Fables 13: Those who would enjoy the wolfish Satisfaction of shovelling it in each Morning must forego the simple Delights of acquiring a Brannigan the Night before.
[US] ‘Sl. Expressions for Drunk’ in New Republic in AS XVI:1 (1941) 9 Mar. 70: [...] on a brannigan.
[US]Phila. Eve. Bulletin 5 Oct. 40/3: Here are a few more terms and definitions from the ‘Racket’ vocabulary: [...] ‘brannigan,’ a spree.
[US]A.J. Pollock Und. Speaks 13/1: Branigan, intoxicated or drunk.
[US]H.A. Smith Life in a Putty Knife Factory (1948) 43: John Darl was ready for another brannigan. He would be orry-eyed before nightfall.
[US]J. Thompson Texas by the Tail (1994) 121: Some brannigan that would attract the attention of the police.
[US]Zachary Strider McGregor-Dorsey ‘Implicit Derivation’ 🌐 Problem 3: Sammy the Sot is on a brannigan again, but after getting a bit too riled up over some bum pull-tabs, the bartender throws him head-over-heels into the gutter.

2. a fight, a violent argument.

[US]W.R. Burnett Asphalt Jungle in Four Novels (1984) 199: He also remembered a violent brannigan they’d had because he’d kidded her cruelly.
P. Edson Associated Press 30 Aug. n.p.: Wave after wave of ugly vituperation [in Congress] [...] Republicans and Democrats alike are guilty of this branigan [W&F].
[US]S. Longstreet Flesh Peddlers (1964) 118: Somebody usually steps in and stops a mean brannigan. This one went too far.
[US]R. Price Clockers 342: A guy got beat on some bad coke [...] Came back with his friends. [...] A whole fucking Brannigan went down.