A sissy wee is when you pee in your knickers, but just a little bit.
not enough to show, but enough to get nervous and to know you have a weak piss-spot.
Ginnie - "Oh fuck, ive just had a sissy wee in my panties! but just a bit. i have such a loose pissing hole."

Jools - "dont worry. you are wearing your large bloomers."
by Crumpets&Tea March 12, 2009
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