1 definition by scarlett_sweeney

A 'better' alternative to using the word 'crazy' or 'insane' to someone. Or just a fun way to call someone crazy. Also, 'mentally jolly' can be used. From the Family Guy episode 'The Fat Guy Strangler'.
"Dr, is my brother really insane?"
"Mrs Griffin, we don't use the word 'insane', we prefer the term 'mentally hilarious'"
by scarlett_sweeney September 1, 2009
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