Green’s Dictionary of Slang

flake (out) v.

[? SE flag, to grow weak, to become exhausted, or US commercial fishing jargon on the flakes, dead, laid out for burial; this refers to the laying out of split fish on wooden racks or flakes]

1. to collapse, from exhaustion, or an excess of drink or drugs; thus flaked out adj.

1942
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2015
[US]L. Kennedy Sub-Lieutenant 39: During the week’s [P.T.] course, two of them broke their ankles; the others usually flaked out from exhaustion before the end of the afternoon .
[UK]A. Sinclair My Friend Judas (1963) 125: I must have flaked out for a few hours, because the next thing I knew was Jimmy shaking me by the shoulders.
[Aus]Aus. Women’s Wkly 3 Nov. 10/4: Now that Surfie talk is flaking.
[Aus]B. Humphries Barry McKenzie [comic strip] in Complete Barry McKenzie (1988) 113: I bunged her an injection and she flaked on me.
[US]J. Roe The Same Old Grind 131: ‘Always flaking out somewhere. Good for nothing, lousy, crippled-up — ’.
[Aus](con. 1941) R. Beilby Gunner 213: She did take your pants off after you’d flaked out again.
[UK](con. 1960s) Nicholson & Smith Spend, Spend, Spend (1978) 154: I can remember one night her flaking out on the couch.
[Ire]J. Morrow Confessions of Proinsias O’Toole 92: Then she wallops into the hard stuff here an’ flakes out. She’s in bed.
[US]E. Folb Runnin’ Down Some Lines 170: I was out before I took three, four hits. [...] I jus’ close’ my eyes, next thang I know, I done flaked!
[Aus]J. Byrell (con. 1959) Up the Cross 90: Mick the Muso had flaked out on the toilet seat.
[Aus]B. Robinson Aussie Bull 23: [T]he Pom staggered down to the beach, flopped on his back beside his wife and ‘flaked’.
[UK]A. Hollinghurst Swimming-Pool Library (1998) 223: I did a few ferocious exercises and then flaked out.
[Aus]M. Walker How to Kiss a Crocodile 89: I turned the key in the door and flaked as soon as I put my head down.
[Aus]S. Maloney Sucked In 193: We waited until he flaked again, then dragged him into a bedroom and dumped him on the bed.
[UK]K. Richards Life 342: This is powerful weed. Funnily enough, I never flaked out.
[Aus]me-stepmums-too-fuckin-hot-mate at www.fakku.net 🌐 I’m gonna flake out.
[Ire]L. McInerney Glorious Heresies 4: [M]en of any age were entitled to flake around the place giving digs to anyone who looked like they might slight them.

2. (US) to recline or lie down, to sleep.

1944
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2000
[US] in Life 17 July 20: Carrier crew men ‘flake out’ on hard deck while planes are far away fighting great air battles [HDAS].
[US]‘Weldon Hill’ Onionhead (1958) 171: ‘Flake out till I come back’.
[Aus]‘Nino Culotta’ Gone Fishin’ 128: Flake out there on the axminster, an’ throw that Wagga rug over you.
[Aus]B. Humphries Barry McKenzie [comic strip] in Complete Barry McKenzie (1988) 42: Do youse reckon I could flake at your dump for the arvo?
[UK]J. Morton Lowspeak.
[UK]Indep. Rev. 9 Oct. 20: I get home and flake out, completely exhausted.
[UK]Indep. Rev. 18 Mar. 20: When I get home, I flake out on the sofa.

3. to go mad; to act eccentrically.

1957
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2012
[US](con. 1943) A. Myrer Big War 167: What did they think held men together [...] kept them from flaking out or cracking up.
[US](con. 1950s) H. Junker ‘The Fifties’ in Eisen Age of Rock 2 (1970) 100: You only got hung up when somebody flaked out on you.
[US](con. Vietnam War) A. Santoli Everything We Had 104: The next thing I heard, he was in a psycho ward. He had just sort of flaked out and gone over the edge.
[US]J. Whedon ‘Prophecy Girl’ 2 June episode of TV series Buffy the Vampire Slayer in Adams Slayer Sl. (2003) 176: You don’t understand I’m not mad. He totally flaked on me.
[US]T. Robinson ‘Roses at His Feet’ in Dirty Words [ebook] The guy tensed, but didn’t flake.

4. (US) to die.

[US]N. Spinrad Bug Jack Barron 15: Give him a contract for a freeze when he flakes out.

5. (US campus) to astound.

[US] oral testimony in Lighter HDAS I.

6. to fail, to let down.

[US]C. Buzzell My War (2006) 23: The Army even pays for you to spend the night at a hotel [...] to make sure your ass doesn’t flake.

7. (US campus) to fail to keep an appointment or other commitment; usu. as flake out on.

1987
199020002010
2014
[US]‘Joe Bob Briggs’ Joe Bob Goes to the Drive-In 18: He can get to the drive-in next week, even if Gus flakes out on him again.
[US]P. Munro Sl. U.
[US]D. Burke Street Talk 2 17: To flake – to be unreliable. He was supposed to pick me up at the airport but he flaked.
[US]Eble Campus Sl. Fall.
[US]C. Eble (ed.) UNC-CH Campus Sl. Spring 2014.

In phrases