The male act of going to the toilet for a wee,piss, number 1, lag, etc but sitting down to complete the act instead of conforming to the standard rules of standing up. This should only be used on rare occasions as a treat so that it doesn't become common place.
Iain: "Where you going Rob?

Rob: "I'm off to treat myself to a sit down wee!"
by BVO1 April 7, 2010
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