A term that is used mostly by African Americans when they want to express their opinions but can not think of the correct words. This phrase was made popular in the YouTube video "Mother fucking Bootleg Fireworks-Subtitled Version"
Before the African American mans friend lights the fireworks he exclaims MONEY UNDER MOUT RUNNIN!
by MorganNormy July 11, 2011
Originates from the expression, "put your money where your mouth is." If you talk shit you better be able to back it up with your money.
So you say you have gansta ass fireworks, money under mout runnin.
by moneymout July 19, 2011