Green’s Dictionary of Slang

(US campus) drunk.

1989		P. Munro Sl. U.
1999		Indep. 21 July 3: Was he [...] absolutely steaming and, maybe, even slaughtered.
2000		Indep. Rev. 20 Apr. 8: Buy half bottles of vodka and gin, and get slaughtered.
2006		Tampa Bay Times (St Petersburg, FL) 29 July 23/4: ‘I can still go out and get slaughtered drunk and enjoy myself’.
2007		L. Redhead Cherry Pie [ebook] ‘Tell me about the staff party.’ ‘Oh god.’ Patsy slumped back [...] r. ‘I was slaughtered’.
2018		I. Welsh Dead Man’s Trousers [15]: A DJ whom he recalls playing lots of cool shit back in the day now sits slaughtered at the bar.