Green’s Dictionary of Slang

1. a general intensive, great, complete, utter.

c.1551		L. Shepherd John Bon in Arber Garner IV 109: Ye are much bound to God for such a spittle holiness. A gallows gift! [F&H].
c.1780		‘The Rover’ in Holloway & Black I (1975) 235: The gallows old whore was always a-growling.
1793		Sporting Mag. Sept. II 342/1: If any one should dare to say I did [i.e. steal a dog], I would tell him he was a gallows liar to his face.
c.1800		‘The Frolicsome Spark’ No. 31 Papers of Francis Place (1819) n.p.: You gallows old greasy arse’d mule.
1829		Clonmel Herald 13 May 4/3: ‘That gallows rake [...] is loaded with money’.
1830		Lytton Paul Clifford III 232: Ah, Dame Lobkin, if so be as our little Paul vas a vith you, it would be a gallows comfort to you in your latter hend!
1836		Bell’s Life in London 6 Mar. 4/1: ‘Vot a gallies shame,’ says he, ‘that there ere handsome young dog [...] should be with a natral pertector’.
1838		‘Paul Pry’ Oddities of London Life I 34: ‘For hitten me the presciousest vop as never was, on my nob, with this here gallus great stick’.
1846		Era (London) 12 Apr. 9/2: Strike me blind, Jack, if I don’t think so [...] but them swells is sich gallows rogues.
1850		Fast Man 8:1 n.p.: [H]e said ‘he witnessed a gallows deal of interruption, and if he saw any more of it, he’d have the party copt and lumbered, by the beadles’.

2. lively, spirited.

c.1800		‘Sandman Joe’ No. 23 Papers of Francis Place (1819) n.p.: While Gallous Joe he wag’d his arse.
c.1811		‘A Leary Mot’ in Farmer Musa Pedestris (1896) 78: Now this brought on a general fight, Lord, what a gallows row.
1823		J. Catnach Tom and Jerry’s Rambles Through Paris 1: For ’tis their hobby every night to raise a gallows row.
1837		A. Greene Glance at N.Y. II v: Come up to-night, and I’ll show you as gallus a piece of calico as any on de floor.
1842		Whip & Satirist of NY & Brooklyn (NY) 26 Feb. n.p.: What has become of gallus Maria.
1842		Comic Almanack July 321: I puts my young ’un in a bran new suit, / And when he’s rigg’d, the gallows little brute / Goes rolling on the bed.
1848		‘Ned Buntline’ Mysteries and Miseries of N.Y. IV 99: She’s a reg’lar gallows gal, she is!
1848		B.A. Baker Glance at N.Y. [play script] Lize: Syksey tried, but I bluffed him off — he’s got to look a little more gallus, like my Mose, afore he can commence to shine.
1850		‘Ned Buntline’ G’hals of N.Y. 15: ‘Yer haven’t made up yer mind, nor nothin’, have yer, Moll?’ asked Ralph, in that peculiar tone which distinguishes the gallus youth of New York from those of all the world. [Ibid.] 19: Yer see, my beauty, I’m bound to shine, as gallus as any pup out, whether you’re agreeable or not. [Ibid.] 86: I’m the gallusest duck out, and know the ropes like a perfect birdee.
1867		‘Johnny Cross’ ‘Happiest Darkeys Out’ Orig. Pontoon Songster 45: Oh we have hired a gallus horse.
1875		M.D. Landon Eli Perkins 56: I’m jes reddy to cruise ’round with pretty, gallus-lookin’ gals any time.
1887		H. Frederic Seth’s Brother’s Wife 322: Some gallus lookin’ young fellers.
1888		S.O. Addy Sheffield Gloss. 84: Gallows, mischievous.
1908		N.Y. Times 25 July in Fleming Unforgettable Season (1981) 135: A gallus band was strewn over the greensward, and the merry musicians played all they knew.
1910		J.M. Synge In Wicklow and West Kerry 4: ‘I asked him where most of the tinkers came from’ [...] ‘They come from every part,’ he said. ‘They’re gallous lads for walking round through the world’ .
1914		Ade ‘The New Fable of the Aerial Performer’ in Ade’s Fables 194: The gallus Offspring hurried to the Metrop to pick the Primroses.
c.1915		in I Opie (ed.) The Singing Game (1988) ‘We are three wee Glasgae molls, / We can let you see, An’ if you hate the one wee moll / Ye’ll hate the heart of three. / Flashy dashy Twelve an' a tanner's gutty boots, / And a’m a gallus moll.
1936		K. Mackenzie Living Rough 175: ‘I see that lassie doon the stair is in the betting to some bloke frae the Cowcaddens.’ ‘Aye, she was always a gallus yin. She was messin’ aboot wi’ yon bloke a long time.’.
1989		H. Leonard Out After Dark 87: To use the words of Synge’s Pegeen Mike, there was ‘a great gap between a gallous story and a dirty deed’.
2021		London Rev. Books 16 Dec. 🌐 ‘That’s a bus conductress...’ ‘Correct. Glamorous all the way. And a wee bit gallus.’.

3. excellent, first-rate, satisfactory, thus gallusest, the very best.

1846		Swell’s Night Guide 60: Them’ere precious gards is gallows quizbey fakements for us fammers.
1848		‘Ned Buntline’ Mysteries and Miseries of N.Y. V 38: We’ve got a gallus machine now, Charley – it’s been to the shop, and looks jist like new!
1848		Boston Blade (Boston, MA) 10 June n.p.: My Mose is the gallusest blood in the market.
1856		G.G. Foster N.Y. by Gas-Light (1990) 174: We hed a gallus time!
1863		Criminal Life (NY) 19 Dec. n.p.: Stop [...] trying to be ‘gallus’ on seven dollars a month.
1907		J.M. Synge Playboy of the Western World Act III: Father Reilly’s after reading it in gallous Latin.
1947		(con. 1870s) F. Weitenkampf Manhattan Kaleidoscope 84: ‘Gallus’ meant something ‘tip-top’.
1973		(con. mid-1960s) J. Patrick Glasgow Gang Observed 113: The ‘gallous gear’ then was: a dark suit with a middle vent of twelve to fourteen inches in the jacket.
2001		C. Brookmyre A Big Boy Did It and Ran Away 74: ‘Aye, that’s gallus,’ was the impressed consensus.