A derogatory expression referring to someone of Belgian or Dutch descent.
I liked Amsterdam but some of those butter mouths pissed me off with their attitude.
by Eddyde March 22, 2008
When you are high and it feels as though you have butter or peanut butter on the roof or your mouth.
"whoa, dude I got really bad butter mouth!"
by xxSlutxx March 03, 2007