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2.
A thumb plumb is when there is a lump of shit left on the thumb after thumbing an arse.
Holy shit, you should have seen the size of the thumb plumb she left.
by Biggaybear April 02, 2013

Words related to Thumb Plumb

ass plumb thumb bum diarea diarhia diaria diarrhea diarria finger
 
1.
When a person jams their finger in their butt hole to prevent diarrhea from spilling into their pants
-Dude, is that guy scratching his ass in class?

-Naw man, that guy's doing a Thumb Plumb
by James Rox Sox January 28, 2009