mistake, n. — Green’s Dictionary of Slang

mistake n.

[euph.]

an unplanned pregnancy and the child that follows.

1957		C. MacInnes City of Spades (1964) 27: Arthur was Mum’s mistake before she met our Dad.
1970		C. Brown Down All the Days 89: Put your little mistake on the sofa there.

SE in slang uses

In phrases

and no mistake (also and no mistake about it, make no mistake)

a general intensifier, certainly, without any doubt.

1828		Sussex Advertiser 14 Apr. 4/3: He backed himself to wein [...] he meant winning, nothing else, ‘and no mistake’.
1830		W.T. Moncrieff Heart of London III iii: covey: What, my little dealer in lace and chapman, Jemmy? james: Andrew Covey! covey: And no mistake!
1831		‘Gallery of 140 Comicalities’ Bell’s Life in London 24 June 2/2: A nice cove this, and no mistake!
1833		[bk title] Regular Thing, And No Mistake.
1835		Sydney Herald 18 June 4/2: [A]s you sport the tip top slang, as you should tip us the office to gammon the queer uns, so up and give it ’em right and left and no mistake.
1843		Comic Almanack Feb. 352: [illus.] It’s quite awful and no mistake.
1847		A. Smith Natural History of the Gent 42: On this dog-cart were four Gents [...] Three had cigars, and the other had a horn; and it was evident that they thought they were ‘doing the fast thing, and no mistake’.
1850		F.E. Smedley Frank Fairlegh (1878) 40: A jolly dodge for a shower of rain, and no mistake.
1857		Glasgow Wkly Times (MO) 19 Nov. 1/5: I love you to distraction and no mistake.
1861		(con. 1840s–50s) H. Mayhew London Labour and London Poor I 417/2: Tip-top swells used to come among us, and no mistake.
1876		C. Hindley Life and Adventures of a Cheap Jack 171: Oh, you’ll have a rare houseful, and no mistake about it.
1889		C. Deveureux Venus in India I 41: You are a good poke! and no mistake!
1898		Boy’s Own Paper 3 Dec. 149: Hurrah! [...] we’ve done it at last, and no mistake!
1900		C. Chesnutt House Behind The Cedars (1995) 117: I wuz jes’ glad to see you gettin’ ’long so fine, dat I wuz, certain sho’ an’ no mistake about it.
1910		H.G. Wells Hist. of Mr Polly (1946) 191: But he’s a Scorcher and no Mistake ... Gramma don’t like him.
1914		M. Glass Potash and Perlmutter 17: He’s got us, Barney. Louis Grossman’s got us and no mistake.
1922		Joyce Ulysses 291: So they started arguing about the point, Bloom saying he wouldn’t and couldn’t and excuse him no offence and all to that and then he said well he’d just take a cigar. Gob, he’s a prudent member and no mistake.
1935		B. Bunting ‘The Well of Lycopolis’ in Complete Poems 37: Whatever I may have done at other times / on the sly / I was in love then and no mistake.
1947		J. Maclaren-Ross Of Love And Hunger 205: You’re a cool customer. And no mistake.
1959		W. Hall Long and the Short and the Tall Act II: They saw you coming, and no mistake.
1971		N. Armfelt Catching Up 106: We’ll see some horticulture in Waitapa, make no mistake!
1992		P. McCabe Butcher Boy (1993) 138: I’d give her the johnny and no mistake.
2004		J. McCourt ‘Vilja de Tanquay Exults’ in Queer Street 306: Just then what some bleedin’ dreary-sof Jerry / Jad to say [...] / Got up / My nose an no mistake.
2016		V. McDermid Out of Bounds (2017) 23: That’d piss on your chips and no mistake.