headcase

/ ˈhɛdˌkeɪs /

noun

1. informal.
   an insane person

Example Sentences

The RFU already runs its Headcase programme to raise awareness of concussion, while rules lowering the legal tackle height in community rugby are due to come into force from July.

From BBC

Mac Siacais also believes those wars are over: "I think anyone who deludes themselves into believing that there is an efficacy in armed struggle in 2023 is either a headcase or someone who has other motives."

From BBC

Unfortunately, if there is a “Headcase Award“ he wins it every year!

From Los Angeles Times

They’d think I was overreacting or making it all up, that I was being some over-dramatic headcase on a rampant crusade to frame some dude after a bout of lousy sex.

From Salon

He starts with the hopeless headcase Gary Thorp, who’s less of a decoy than Lee presumed.

From New York Times