adj. (slang): A combined state of mental agitation and physical volatility. It's use may provide warning that the individual it describes has lost all self-control and cannot be reasoned with. Can refer to either a chronic or temporary condition.
by maximo hudson January 20, 2009
Family: "So, did he have a psychotic break? Or is he manic/depressive?"
Doctor: "No. I'm sorry. Your son is bat shit crazy."
by Brainiac March 02, 2005
by Lorraine Bates July 31, 2006
by Frankie Diva Cat August 11, 2010
It is the psychological state of a man who loses all social etiquette from an experience so inexplicably ridiculously incomprehensible and thus brashly reacts out of character.
Hey, did you hear about Tan getting the lowest grade in the Final Year Aircraft Design Group Project? He went Bat-Shit Nagasaki and stabbed scrappy with his own prosthetic leg.
by Slap dog gamillionaire November 30, 2016
Bat Shit Sane means that you are so sane that the Bat Shit Crazy people can't deal with you. Bat shit Sane people are knowledgeable on too many topics that they baffle ordinary people who cannot process anything other than Bat Shit Crazy shit. Unfortunately, the Bat Shit Sane are directly identified as the same as Bat Shit Crazy.
by Clperkins December 21, 2016
Crazy to a degree bordering on complete insanity. The state in which one makes decisions which make the exact opposite of sense.
See also: bat-shit
by DJ Bitterbarn August 12, 2004