Does not mean an unfirm bottom, but it means a person who is very lazy
I had to fire David as he was a slack arse
by Windy28 September 4, 2009
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A word used for someone who receives anal a lot.
That girl Wendy over there, I heard the whole football team has put it up her arse. She must be a right slack arse.
by Yeahyea June 6, 2015
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Term used to describe someone who is known for dropping an inordinate number of farts, usually to their to own delight.
Eh, you shit?
Yeah! (gleefully)
You slack-arsed bastard!
by ant August 9, 2004
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