When you laugh really hard, so you nearly wet yourself, your gunna need some coaster pants! The origin of this phrase is never clear, but we have a gorgeous liverpool bloke to thanks for it somehwere down the line...
The term mortadella pants can be applied to any overweight person wearing overly tight jeans. Their legs take on the appearance of a mortadella sausage wrapped extremely tightly. An acceptable and perhaps equally humorous alternative is "kielbasa trousers".
Check out alex over there in his fuckin mortadella pants, fat scenester oughta grow up already
Pants that are worn out on a friday or saturday night. These pants shine brighter than a disco ball and have the elasticity that may cause serious whip lash.