Green’s Dictionary of Slang

squeal (on) v.

[late 19C+ use mainly US, but note Edgar Wallace title, The Squealer (1927)]

1. to complain.

[UK]Leaves from Diary of Celebrated Burglar 139/1: I’ll taik kair ’e doan’t squeal anny abeowt it, else I’ll breeak ’is owl jaw fur ’im.
[US]J. O’Connor Wanderings of a Vagabond 211: This is the division made, unless the ‘sucker’ happens to be some influential person, and fleeced while drunk, and who, when sober, will ‘squeal’ for his money.
[US]Number 1500 Life In Sing Sing 262: I don’t squeal. I had a good run in ’Frisco and I’ve breathed easy ever since.
[Aus]Bulletin (Sydney) 12 Dec. 29/2: ‘This has cost enough to square the Legislature of the Noo York State, an’ I’m goin’ to squeal.’ He says: ‘For John the Baptist’s sake,’ he says, ‘don’t squeal yet. Gimme another pay.’ [...] ‘Then I squealed so that you could hear me in Texas.’.
[Aus]Smith’s Wkly (Sydney) 11 Aug. 15/4: The possum never squealed either. It was one of the neatest jobs I ever ’andled.
[US](con. 1900s) S. Lewis Elmer Gantry 152: I suppose you’ve gone squealing to your old man and the old woman!
[UK]E. Glyn Flirt and Flapper 98: Flapper: He’s grateful to me [...] he’s never squealed once .

2. to own up.

[US]W.T. Porter Quarter Race in Kentucky and Other Sketches 45: I got his head under my arm an I made him squeal immediately.
[US]Bartlett Dict. Americanisms (4th edn) 797: Squeal, [...] to ‘throw up the sponge’.
[US]P. & T. Casey Gay-cat 238: Gonna beef where it’s hid? Gonna squeal ef Slim’s boy’s got it or not?
[UK]P. Cheyney Dames Don’t Care (1960) 99: I can make her squeal the rest of the stuff about the counterfeitin’.
[US]N. Algren Neon Wilderness (1986) 106: But sick as I was, I didn’t squeal about the four pennies.

3. to inform against one’s partners, esp. partners in crime.

[UK]Hotten Sl. Dict.
[US]Nat. Police Gaz. (NY) 7 Sept. n.p.: He would squeal like a pig if the ‘collar’ was put on him.
[US]G.P. Burnham Memoirs of the US Secret Service 86: He located the ‘boodle,’ and ‘squealed’ on his pals.
[US]S.A. Mackeever Glimpses of Gotham and City Characters 55/1: I would be a despicable wretch indeed to repay the courtesy which made the experience possible by ‘squealing’ on those I met. I believe they call it ‘squealing’.
[US]World (N.Y.) 30 June 10/4: If they don’t get a lawyer for me I’ll squeal on the whole business.
[Aus]Bulletin (Sydney) 2 Aug. 10/1: O Blessed Interpreter! / Scene – Suburban Police-court / [...] Witness: ‘Why, he meant he’d biff me if I squealed or turned dorg on him.’.
[US]J. Flynt Tramping with Tramps 392: beefer: one who ‘squeals’ on, or gives away, a tramp or criminal.
[US]H. Green Actors’ Boarding House (1906) 85: One of the gang had squealed on the big job in Frisco.
[US]E. O’Neill The Web in Ten ‘Lost’ Plays (1995) 63: Yuh swear yuh won’t squeal on me?
[US]S. Lewis Babbitt (1974) 191: If I catch you knocking me to any other firm, I’ll squeal all I know about you.
[US]R. Sale ‘A Nose for News’ in Goulart (1967) 214: It’s funny how fear will make a guy squeal on his own mother.
[US]N. Algren Man with the Golden Arm 287: Cats are all stooges anyhow [...] a dog’ll never squeal on a pal.
[US]Mad mag. June 12: Was you who squealed on me, / And sent me to the local pen.
[UK]R. Cook Crust on its Uppers 106: Dummies don’t squeal.
[US]L. Bruce How to Talk Dirty 10: Miss Bostaug hadn’t ‘squealed’ on me.
[UK]A. Sillitoe Start in Life (1979) 100: He’d been remanded in custody, which meant they were trying to make him squeal.
[US](con. 1967) E. Spencer Welcome to Vietnam (1989) 9: The guy was macho. He didn’t squeal.
[UK]J. Cameron Vinnie Got Blown Away 146: But squeal the screws on some aggravation up the recess or bit of crack on visits, well out of order.
67 ‘Live Corn’ [lyrics] If suttin get got I know my niggas won’t squeal.

4. to report a crime to the police or any other authority.

[US]Nat. Police Gaz. (NY) 27 Apr. 6/3: [He] came down loser and very sullen. He growled and then threatened to squeal if he didn’t get a part of the play returned.
[US]Ade Forty Modern Fables 36: He was a Good Fellow and would not go and Squeal to the Faculty.
[US]G. Bronson-Howard Enemy to Society 211: Some of those fearless mutts who are ashamed to fight less than three at a time but start to ‘squeal’ the minute a copper taps them on the shoulder.
[US](con. 1920s) J.T. Farrell Judgement Day in Studs Lonigan (1936) 520: The tightening net of evidence. The blonde squealing.
[Aus]Queenslander (Brisbane) 2 July 4/4: So, out to crop the wisdom I did sow, And with much daring took a ‘gay’ in tow. / But this was all the harvest that I reaped, / I touch the ‘mug’ - he squeals - and in I go!
[Aus]F.J. Hardy ‘The Load of Wood’ in Man From Clinkapella 9: Keep yer trap shut. If yer squeal about this, I’ll kick yer bloody guts in!
[UK]A. Sillitoe Sat. Night and Sun. Morning 164: Then you’d squeal like a stuck pig.
[US]M. Spillane Return of the Hood 64: Stoolies who squeal to ingratiate themselves with the cops.
[Ire]P. O’Farrell Book of Irish Soldiers’ Jokes 12: Bandmaster: ‘Do you know Who Killed Cock Robin?’ Applicant: ‘I do. But I’d never squeal on a bird.’.
[US]C. Hiaasen Tourist Season (1987) 170: You weren’t thinking about squealing, were you?
[US]G. Sikes 8 Ball Chicks (1998) 52: Satisfied the child wouldn’t squeal, Jade looked at Wanda accusingly.

In compounds

squeal rule (n.) (also squeal law)

(US) the law requiring parental notification when an underage girl applies for a prescription for contraceptives.

[US]H. Rawson Dict. of Invective (1991) 372: We have challenged [the Reagan Administration’s] insistence on promulgating a rule requiring family planning clinics to squeal on teen-age patrons to their parents (editorial, New York Times, 1/13/83). By labeling the requirement a squeal rule, opponents of the plan stacked the argument in their favor.