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8.
Used to describe a two liter bottle of cider.
What do you want from the off licence?
A big dirty mate!
by Rycy May 09, 2008
 
9.
Any amount of cocaine
Let's do a Big Dirty before the concert
by --Mick-- November 20, 2005
 
10.
to have or to take a aqua lung
i took a massive big dirty last night
by lance white jr. June 07, 2007