Green’s Dictionary of Slang

1. vigorous.

1821–5		‘Bill Truck’ Man o’ War’s Man (1843) 216: Favoured as she was with a cracking breeze, the saucy Tottumfog speedily gained the latitude.
1833		C.A. Davis Letters of Major J. Downing (1835) 28: If you don’t hear of cracking work down there, that will make ’em stare, I’m mistaken.
1934		Wodehouse Right Ho, Jeeves 209: She was setting a cracking pace.
1960		E. De Roo Big Rumble 61: When things are crackin’, I get a chance for tips waitin’ on tables.
1971		N. Armfelt Catching Up 225: She woke up with the most cracking headache she had ever had.
1999		Indep. Rev. 13 Oct. 10: Lynne Parker directs at a cracking pace.

2. excellent, first-rate.

1859		S. Smith My Thirty Years Out of the Senate (1860) 183: The President’s message to Congress makes cracking work here.
1899		Ade Fables in Sl. (1902) 82: He had 240 acres of crackin’ Corn Land (all tiled).
1902		C.L. Cullen More Ex-Tank Tales 22: They sell ’em f’r real antiques, y’see, and they get crackin’ prices.
1912		Van Loan ‘The Comeback’ in Ten-Thousand-Dollar Arm 208: Give me one more cracking good pitcher.
1918		‘Commander’ Clear the Decks! 115: He was a cracking good division officer.
1939		W. Winchell On Broadway 7 Aug. [synd. col.] ‘Beau Geste’ [...] It’s a cracking meller.
1947		G. Fairlie Bulldog Drummond Stands Fast 43: Cast your wizard eye over the little Ford [...] she’s in cracking order.
1951		A. Buckeridge Jennings Follows a Clue (1967) 69: I’ve got a cracking idea!
1963		B. Naughton Alfie I ii: She’d never make number one [...] — but she’s a crackin’ little standby.
1967		E. Shepard Doom Pussy 35: The Vietnamese make cracking good pilots.
1984		A. Sayle Train to Hell 53: What a cracking match that was.
1995		D. Lodge Therapy (1996) 61: ‘Cracking programme the other night,’ said the milkman.
2003		N. Griffiths Stump 93: Should a brought some rolls an some brown sauce. Could’ve had a crackin friggin barbie, lar, eh?
2015		‘Elvis Costello’ Unfaithful Music 91: [T]he Lennon-McCartney compositions ‘Love of the Loved’ and ‘It’s for You,’ both of them cracking songs.
2021		Twitter 3 Oct. 🌐 I asked a male comedian not to post ‘cracking norks’ alongside this book cover.
2024		J. Meades Empty Wigs (t/s) 120: The Japanese have some tasty tricks up their sleeves. Latinas - cracking. In fact they're all cracking.

3. a general intensifier, i.e. utter, absolute.

1943		J. Lees-Milne Ancestral Voices diary 31 July (1975) 218: I learned several of her expressions: [...] a mild bore being an ‘Aubusson’, a real bore a ‘Kidderminster’, and a cracking bore a ‘velvet pile’.
1958		M. Allingham Hide My Eyes (1960) 198: For God’s sake, Polly, be quiet, and don’t talk such cracking rot.