be on the piss
be (out) on the piss
rude slang To go out and drink alcohol. Primarily heard in UK, Australia. My friends and I were out on the piss last night, so I hardly remember anything at all.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
be on the ˈpiss(British English, taboo, slang) be out at a pub, club, etc. and drinking a large amount of alcohol: I’m not sure if Jerry will be at work today — he was out on the piss with his mates last night.
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