Meaning
What does Batshit Crazy mean?
Batshit crazy, sometimes also called guano loco is an expression for people, who have so little going on in their heads, that it is inhabited and utterly soiled by bats in there.
The phrase is just another way of saying someone is a fool, a dangerously insane or delusional character; someone who has some sand in the machine.
Origin
What's the origin of Batshit Crazy?
The expression was used with the same meaning already back in the early 20th century, under the form of batty.
The term came from the phrase bats in the belfry, which is a bell tower.
In essence, the analogy likens a person to an abandoned church, which’s bell tower is infested and marked by bats and their excrement.
The term “batshit” appeared as a synonym for the word bullshit around the 1960’s and und the 1980’s, the phrase “batshit crazy” had appeared in the English lexicon of expressions.
Spread & Usage
How did Batshit Crazy spread?
“Batshit crazy” became widely popular over the years, remaining in use up to this day, both in real life conversations, as well as online, be it social media posts, articles or other content.
The phrase was first defined on Urban Dictionary in 2003, with a bunch of other definitions and entries uploaded to the site since then.

External resources
- TheMastermindShowBlog – What Does The Term “Bat Shit Crazy” Mean?