The word batshit can be used to refer to the fecal matter of bats but more often it is used in a phrase to say that someone is crazy. Saying that one is batshit insane or batshit crazy is generally interpretted to mean that person is disconnected from reality, to the point that he or she is impossible to deal with in a normal manner. The term carries a negative connatation. Example: "Don't talk to Sheila. She's batshit insane." or "I called the cable guy again, didn't understand a damn thing he said. That fucker is batshit crazy!" For the flying mammal see bat. ...

Because it uses the term shit batshit is not acceptable in formal speech or writing, and is only used colloquially. Other words with similar meanings but are less offensive and more acceptable to use are: Off his or her rocker, out of it, out of his mind, has left the building, not playing with a full deck, a few bricks short a load, deranged, looney or the terms crazy or insane without the addition of batshit. In Britain batty, dodgy and mad are also used but are less common in America English, unless they are used to imitate or make fun of British speech. Clinical terms for conditions that could make someone "batshit crazy" and are used and understood by most English speakers are insanity, schizophrenia and bipolar disorder also known as manic depressive disorder. There are also many clinical conditions that a batshit crazy person could suffer from but those terms aren't often used outside of the fields of psychology and psychiatry. Shit is a vernacular word in Modern English denoting feces, the byproduct of digestion. ...