a bacterial disease
skinny white boy who looks like he has down syndrome = firth
av sam excellent 4 december 2003
The process of being penetrated in the booty hole while giving birth.
Christopher is a firth baby.
av CupDude 17 februari 2009
A derivative of filth. Meaning lower than specks of dust on your shoes.
Man, that is pure firth!
av Crismon 16 juni 2003