Green’s Dictionary of Slang

1. in pl., dificulties, usu. financial ones.

1860		R. Nicholson Rogue’s Progress (1966) 43: Soon after 1832, he got into ‘diffs’, and his residence was divided between the King’s Bench and the Fleet Prison.
1894		G.A. Sala Things I Have Seen II 63: For gentlemen in difficulties arrested in the county of Surrey there was a single spunging-house in a street somewhere off the Blackfriars Road. I remember visiting a friend there once, who told me that the apartments were extremely comfortable. The sheriff’s officer was an accomplished whist player, and he had a musical daughter who used to play and sing to the gentleman in ‘diffs.’.

2. (also diff) the difference, e.g. no dif(f), that’s the dif; what’s the dif?

1858		London Gaz. 15 June n.p.: War office [...] 4th Drag[oon] G[uar]ds: Capt J.E. Brodhurst, fron the 40th F[oo]t, paying the diff, v Shawe, who ex, receiving the diff.
c.1864		‘Bear-Ass Ride’ in Rakish Rhymer (1917) 151: It’s not a diff of bitterance to either you or I— / Big p—ks, little p—ks, all are getting high.
1868		Marysville Enterprise (KS) 2 May 2/3: What’s the diff between Orton’ s Female Cornet band and a cow?
1892		in Punch 26 Nov. 252: Of course yourn was respectable; mine wosn’t; there’s the diff.!
1902		Ade Girl Proposition 86: Tessie didn’t know the diff between a Manor House and a Chop House.
1908		B. Fisher A. Mutt in Blackbeard Compilation (1977) 51: Poor Jeffries is always the fall guy, but what’s the dif? He’s just as happy as if he had good sense.
1910		O. Johnson Varmint 58: What’s the diff?
1911		B. Fisher Mutt & Jeff 10 Aug. [synd. strip] He may have a few more brain cells [...] but what’s the dif?
1914		S. Lewis Our Mr Wrenn (1936) 68: It wouldn’t make any dif. what they met as long as they were fighting together.
1919		E. Ferber ‘Un Morso doo Pang’ in One Basket (1947) 82: What’s the diff? You had to make the best of it.
1923		D. Hammett ‘The Second-Story Angel’ in Nightmare Town (2001) 218: Don’t make no diff’ whether you make charges against her or not.
1923		Gippsland Times (Vic.) 1 Oct. 5/3: An’ w’en I ain’t too busy / Ennythink wot’s wrong with Lizzie, / I cud fix up in a trizzie, / It don’t make no diff ter me.
1924		P. Marks Plastic Age 128: ‘I don’t understand.’ ‘Oh, what’s the dif?’.
1937		D. Fuchs Low Company 137: It makes no diff.
1942		‘Marienne’ ‘Solid Meddlin’ in People’s Voice (NY) 7 Mar. 33/1: Heppin’ wide-eyed glammah gals to the dif’ between a second lewy and a cropy.
1947		B. Schulberg Harder They Fall (1971) 111: What’s the diff. It’s only money.
1950		‘Hal Ellson’ Tomboy (1952) 85: ‘What’s the diff?’ Tomboy said.
1953		W. Brown Monkey On My Back (1954) 100: The only dif is I’ll sell it to him cheaper and give him good H.
1960		E. De Roo Big Rumble 92: I’ll meet ya by the flag pole, and you’ll know the diff ’cause I’m the one with the shape.
1975		L. Rosten Dear ‘Herm’ 148: You would never believe the diff it has made.
1977		G.F. Newman A Prisoner’s Tale 114: What’s the fucking dif’?
1984		Furious Five ‘Step Off’ 🎵 There is no diff between me and you / Except I look good and you look blue.
1999		Dr Dre ‘Some L.A. Shit’ 🎵 I was raised in the hood called what-the-dif.
2005		J. Stahl I, Fatty 98: The big diff: highbrows loved Charlie.

3. (Aus./N.Z.) the diferential gear on a motorcar.

1968		D. O’Grady A Bottle of Sandwiches 152: Got a few diffs an’ gear boxes.
1992		A. Duff One Night Out Stealing 28: These car freaks they won’t play Scrabble [...] too many words they don’t know. You get em on diffs and stuff and they’re geniuses.
2000–02		Macquarie Dict. 🌐 diff noun [...] 2. an engine differential: Me car needs a new diff.
2003		McGill Reed Dict. of N.Z. Sl.