go off the deep end

Cultural  

1. To act recklessly or hysterically: “The students were behaving themselves at the party, but then a couple of kids started to go off the deep end.”

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go off the deep end Idioms  

1. Become unduly excited, overwrought, or angry. For example, When he heard about John's smashing into his car, he went off the deep end . [c. 1920] Also see in deep , def. 2.

2. Be irrationally carried away, act irresponsibly or heedlessly. For example, Just because you like her looks doesn't mean you should go off the deep end and propose . [c. 1920] In both of these colloquial usages deep end alludes to the deep end of a swimming pool.

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Related Words

• freak out
• go off
• lose it