Green’s Dictionary of Slang

1. lit. to urinate on oneself.

1797		Bridges Burlesque Homer (4th edn) II 16: What shame! [...] / Ye all bepiss’d yourselves for fear.
1953		W. Eyster Far from the Customary Skies 112: Brooklyn says you pissed yourself.
1965		G. Melly Owning Up (1974) 117: There I was [...] the gude whisky running down in a stream betwen ma legs and making a pool on the street. ‘Have you pussed ye’sel?’ he asks.
1974		P. Larkin ‘The Old Fools’ in High Windows 19: You keep on pissing yourself, and can’t remember.
1978		S. King Stand (1990) 1221: He was just about pissing himself.
1988		Herald Rev. (Decatur, IL) 7 Feb. 3/3: Bean’r pissed herself.
1996		J. Baker Death Minus Zero (1998) 160: They start bawling, or even piss in their knickers [...] Jesus, people start pissing themselves, you just want to pack up and go home.
2002		J. Lerner You Got Nothing Coming 205: So you did, in fact, proceed to piss yourself!
2008		A. Wheatle Dirty South 180: I couldn’t walk in a straight line and I pissed myself twice.
2008		J. Lansdale Leather Maiden 44: I was lying on top of the sheets, having pissed myself. The room smelled of urine and alcohol.
2021		S.A. Crosby Razorblade Tears 54: Buddy Lee heard the pitter-patter of water hitting the laminated floor. [...] ‘He just pissed himself’.

2. to be utterly terrified, whether lit. causing urination or not.

1960		J.R. Ackerley We Think The World Of You (1971) 123: ‘Did he get into trouble?’ ‘No, but ’e didn’t half piss ‘isself.’.
1977		K. Gilbert Living Black 300: They talk fight but piss themselves in fear.
1987		(con. 1920s) L. Redmond Emerald Square 57: The poor man was pissing himself with fright.
2000		R.G. Barrett Leaving Bondi (2013) [ebook] ‘Don’t piss yourself when you see what happens’.
2010		(con. 1973) C. Stella Johnny Porno 55: ‘Let’s not get carried away’ [...] ‘Don’t piss yourself’, Hastings said.

3. to laugh uproariously; usu. the urination is just fig.

1945		‘Lament to a Beaufort’ in Mess Songs & Rhymes of the RAAF 19: But when he sees those Beauforts, all U/S two weeks after, / He smartly changes from shitting, and pissed himself with laughter.
1946		P. Larkin letter 17 July in Thwaite Sel. Letters (1992) 119: Well thanks for Your letar, you can certanly Spinn a yarn, I was fare peng myself at the Finnish.
1958		(con. 1940s) B. Behan Borstal Boy 249: Old Tessie just looked down at ’im and pisses ‘imself laughing.
1962		F. Norman Guntz 109: I went on, almost pissing myself with laughter.
1976		D. Ireland Glass Canoe (1982) 57: Danny’s pissing himself laughing by this time.
1981		S. Berkoff Decadence in Decadence and Other Plays (1985) 15: Pissed myself laughing.
1987		(con. 1920s) L. Redmond Emerald Square 100: One boy, Dessy O’Connor in the corner, pissed himself, laughing.
1992		M. Coleman Fatty 118: ‘He was a nice but he had the funniest head I’ve ever seen. I was pissing myself’.
1993		I. Welsh Trainspotting 40: Nina thought that she would piss herself.
2000		Guardian Guide 1–6 Jan. 44: The kids would still be pissing themselves laughing.
2013		K. Sampson Killing Pool 139: ‘We need to talk about Kalan.’ He’s not exactly pissing himself. ‘Yes, I’m well aware...’.
2020		G. Armstrong Young Team 15: They’re aw pishin thirsels at the eld cunt.