Maniac

The term maniac can mean more than one thing:

(archaic) A maniac is a person who exhibits the behaviour known as mania.
(slang) A person who acts in a wild or harmful manner.
A poker player who plays in a very "loose-aggressive" style, making large bets and bluffing frequently.
Maniac can also refer to the disorganized offender classification of serial killer.
MANIAC is also the name of the MANIAC I computer.
Maniac is the callsign of the human pilot Todd "Maniac" Marshall in the fictional Wing Commander universe.
Maniac (real name: Sven Erik Kristiansen) was the vocalist for Norwegian black metal band, Mayhem between 1986 and 1988, and again from 1995 until 2004.
"Maniac" is a song from the movie Flashdance by Michael Sembello.
"Maniac" is also the title of several unrelated films. See: Maniac (film).
Maniac meaning an insane person.