Symptoms may include increased speech, a rush of thoughts/hard to follow thought trains, compulsive movements (Finger tapping, dancing, darting head movements etc.) excessive energy, reduced need to sleep (Sometimes going for a week or more without sleeping) and increased appetite.
Can also include boosted confidence, a feeling of almost euphoric happiness, increased production of adrenalin and/or endorphins, excessive or lack of libido and a highly reduced sense or fear of danger.
Often highly intelligent and eccentric, though hard to talk to without going far off topic or spending hours listening to one giant spontanious rant.
Most common in people with the medical conditions mania, manic depression or hypomania.
2. A descriptor applied to people meaning to display a near obsessive love of something. See also: otaku
2. Harry is such a footballmaniac. He's been to every home game this season and won't stop talking about it. He's even painted his car in his teams colors!
2nd person: "Oh yeah. I'm a maniac!"