Frude actually means (Fucking rude) as in "Filthy Fucking rude"! It's a word my boyfriend uses when others are around. Comes in handy when refering to the previous nights antic's when parents or children are present lol.
frude fight is when men and women join in a cafeteria, strip butt naked and throw food at each other.
kind of like a food fight but that involves... clothing.
that frude fight the staff had was epic. I heard it took 5 hours for the janitor to clean the cafeteria!!