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headcase

British  
/ ˈhɛdˌkeɪs /

noun

  1. informal an insane person

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

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

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

From New York Times

Noel: You have got to have a headcase on the drums and Mario could also join in with a rap every now and again.

From BBC