To become wildly excited, extremely upset, or mentally unbalanced, depending on context. Can describe positive excitement, negative emotional breakdown, or temporary loss of rational behavior.
The word 'crazy' originally meant 'cracked' or 'flawed' in the 1570s, referring to objects with cracks. By the 1600s, it was applied to minds that were 'cracked' or broken. 'Go crazy' emerged as a way to describe the transition from normal to abnormal mental states, whether temporary or permanent.
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