This basically is a word that means a very large cunt, or disrespectful woman. A butfuckingdundercunt is to be used on the spur of the moment and not to be used towards anything other than a female.
Woman: Go make me a sandwich!
Man: Shut up you butfuckingdundercunt!

the male took action because the woman actually said to make him a sandwich.... im pretty sure men dont make sandwiches, so he took initiative.
by Dylan!!! June 14, 2011
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