In professional wrestling, wrestler Brock Lesnar's finisher. It has also been described as a spiral bomb. Instructions on how to perform the F5 is listed under the spiral bomb node. Frequently, finishers are other moves with fancy names. The spiral bomb, however, is still a very impressive move, at least in terms of strength if not skill and agility.
Impressively, Brock Lesnar has performed this move on the Big Show, who is enormous.
Brock Lesnar has confirmed my suspicion that the name F5 is in reference to the highest category tornado. He said in a radio interview that someone noted the move looked like a tornado, so he named it F5.