To write something negative on someone's Facebook wall.
I swear, if you post that picture of me, I'm going to piss on your wall.
by Slouching Buddha October 22, 2010
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To have spent money buying alcohol to drink.

Came across it c.50years ago when a teenager on a building site.
I think it may be where "pissed up" meaning to be drunk came from.
Foreman: "It's Monday and he asked for a sub, he got paid on Friday! All his wages pissed up the wall"
Me: "What's pissed up the wall?"
Foreman: "What? Oh, it's going out and getting drunk."
Me: ....?
Foreman: "Staggering home they'll feel like a piss and go against the nearest wall: what they'd spent their wages on just gets pissed up the wall."
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