A Mexican Mourning is the painful feeling and diarrhea you have when you wake up the next morning from a Mexican Dinner. Its a cultural sfacklefest! (Sfackle - The art of projecting feces with the aid of a fart, a fart spackle).
I was totally having a wet dream when I was abruptly awoken by a Mexican Mourning!
One morning in Cancun, i drank tap water and in 5 minutes i had a Mexican Mourning knocking at my sphincter...
Lucky, one of the 2 GIRLS didnt have Mexican for dinner before playing with the cup...(Mexican mourning would have made that video anti-viral)