Noun

1. One who drives excessively quickly, loudly or irresponsibly; a street drag racer often driving heavily-customized cars, perhaps imitative of the sound of these.
   • 2009, Victoria Police Home Page, State of Victoria

     Police have impounded an average of 10 cars a day since hoon laws were introduced by the State Government in June 2006.

2. A lout.

Verb

1. To drive excessively quickly, loudly or irresponsibly.