batshit

Fecal matter produced by bats.

Extreme irrationality or unreasonableness, insanity, craziness.

Yvette Cooper, the shadow home secretary, suggested Cleverly had previously privately referred to the Rwanda plan as “batshit”, a jibe not explicitly denied by Cleverly.

Extremely irrational or unreasonable, insane, crazy.

Don't take any courses from that professor. She's completely batshit.

And what the fuck are you doing on TV anyhow? You know I get calls from back home every fuckin day, they think you went batshit!

Used as an intensifier, particularly for insane or synonyms.

When we heard about it he went batshit nuts.