psycho

adj

1. (colloquial, derogatory)Psychotic, psychopathic, or (broadly) otherwise insane.

   “That psycho jawn had snuck a pistol into the gym while we was practicing and started shooting shit up like she was some kinda hot female action hero.”

   “Oh, she's sweet but a psycho / A little bit psycho / At night she's screamin' / "I'm-ma-ma-ma out my mind"”

noun

1. (derogatory, slang)A person who is psychotic, psychopathic, or (broadly) otherwise insane.

   “The loony bin up on the hill is full of psychos.”

   “Oh, she's hot but a psycho / So left but she's right, though / At night she's screamin' / "I'm-ma-ma-ma out my mind"”

2. (broadly, derogatory, slang)A person who acts in a bizarre or dangerous manner.

   “She complained that he was a psycho for driving at such a high speed in heavy traffic.”

3. (informal, uncountable)A class, at a college or university, in which psychology is taught.

   “I've got anthro, socio, lunch, and psycho.”