George Clooney auditioned five times for the role of hustler JD which turned out to be Brad breakout In what movie?

The movie you're thinking of is "Thelma & Louise".

While George Clooney auditioned for the role of J.D., the charming hustler who befriends Thelma and Louise, he wasn't chosen for the part. It ultimately went to Brad Pitt, who, as you mentioned, used it as his breakout role.