The term Biggest Possible Oof refers to the biggest and loudest Oof possible in this Universe. This is even bigger than the MEGA OOF. The term can also be used as onomatopoeia.
Bro 1: Yo bro, ya girl just cheated on ya
Bro 2: MEGA OOF
Bro 1: Also Trump got president
Bro 2: Biggest Possible Oof