Green’s Dictionary of Slang

1. to admit, to confess; esp. as fess up (to).

1860		T. Haliburton Season Ticket 250: Yes, half a dollar a day is poor pay, but I must ’fess it’s berry poor preachin’.
1871		O.E. Wood West Point Scrap-Book 64: When you and I and Benny, and all the others too, / Are called before the ‘final board’ our course of life to view, / May we never ‘fess’ on any point, but straight be told to go, / And join the army of the blest at Benny Havens’, oh!
1899		J. Flynt Tramping with Tramps 342: ’Cause to ’fess up, Cig, I ain’t very proud o’ this bummin’.
1903		‘Hugh McHugh’ Out for the Coin 104: Then and there I ’fessed up everything from Alpha to Omega.
1909		A. Bierce letter 1 Nov. in Pope Letters of Ambrose Bierce (1922) 157: You better ’fess up to your young friend.
1914		E. Wittmann ‘Clipped Words’ in DN IV:ii 142: fess. To confess, own up.
1929		S.J. Perelman Dawn Ginsbergh’s Revenge 84: They ‘’fessed’ up that their name was not King after all.
1936		(con. 1830s–60s) ‘Miles Franklin’ All That Swagger 325: He means more to you than any one else in the world: ’fess up.
1939		D. Burley N.Y. Amsterdam News 22 July 16: Come, you, and you and you: ’fess up!
1947		N. Marsh Final Curtain (1958) 189: I’ve come to ‘fess up,’ like a good boy.
1959		E. De Roo Go, Man, Go! 45: Come on—fess up. Vomit on the table. I hear you’re feeding him special soup!
1967		I. Rosenthal Sheeper 223: Tell the truth Smilowitz, ’fess up.
1975		J. Wambaugh Choirboys (1976) 116: Okay, fellas. Let’s fess up. Who farted? [...] But a funny thing happened: nobody fessed up.
1986		S. King It (1987) 304: Fess up, Eds – who built the dam?
1992		R.C. Cruz Straight Outta Compton 44: ‘Why don’t you just fess up?’ I said.
2004		K. Rinehart Big Clean 6: Nevertheless, it’s time to fess up to the mess your pad is in and own it.
2006		B. Matthews Intractable [ebook] She broke down and fessed up the whole story.
2010		A. Steinberg Running the Books 328: Unless you want to fess up.
2011		J.J. Connolly Viva La Madness 360: It’s also time to fess up — get a confessional as to why two geezers are trying to kill Sister Bridget.
2015		S. King Finders Keepers (2016) 298: ‘Out with it, Peter. Fess up’ [...] Peter does not fess up. To fesss up is to die.
2016		A. Wheatle Crongton Knights 200: ‘I was gonna fess up [...] It was so messed up’.
2018		C. Hammer Scrublands [ebook] When those girls are ghauled out of that dam [...] it’s time to fess up’.
2024		J. Meades Empty Wigs (t/s) 821: What would be the point in me fessing up to my part.

2. (US campus) to fail in one’s recitation, to admit that one has not prepared the lesson’s work.

1834		in Military and Naval Mag. of US III 25 Mar. n.p.: My first appearance before the Blackboard—that terror to all ‘fifth-section men;’ that abomination of him who has to ’fess [DA].
1856		B.H. Hall College Words (rev. edn) 195: fess. Probably abbreviated for Confess [...] to fail in reciting; to silently request the teacher not to put farther queries.
1878		H.O. Flipper Colored Cadet at West Point 53: ‘Fessed,’ ‘fessed cold,’ ‘fessed frigid,’ ‘fessed out,’ and ‘fessed through.’ — Made a bad recitation, failed.
1937		Banning West Point Today 295: Cadet Lingo [...] Fes, v. To fail completely in a recitation [DA].

3. (US black) to back down or decline.

1995

L. Stavsky et al. A2Z.

4. to complain, to whinge [suggesting an image of insincere or excessive confession, i.e. verbal manipulation].

1984

Beastie Boys ‘Party’s Getting Rough’ 🎵 You’re just fessin’, man, I don’t even want to hear about it.

5. to annoy or irritate someone [suggesting an image of insincere or excessive confession, i.e. verbal manipulation].

1992

D. Burke Street Talk 2 49: Don’t fess with me or do and you’re through.