bonkers
/ˈbɒŋkəz
/adjective [predicative] informal, chiefly British
Mad; crazy: you’re stark raving bonkers!...
- Good god, he really has gone stark raving bonkers, hasn't he?
- If your neighbour's dogs barking is driving you bonkers, use a video camera to tape the mutt howling.
- She most likely thought I was stark raving bonkers as I told the tale of my worries about leaving the gas on.
Origin
1940s: of unknown origin.