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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Example Sentences

“People have problems, but you don’t expect them to go off the deep end like that,” Letarte said.

From Washington Times • Oct. 27, 2023

Her untimely death prompts a heartbroken Padraic to go off the deep end.

From Washington Post • Mar. 1, 2023

"I didn't go off the deep end," he explained.

From Fox News • Apr. 19, 2019

He probably senses she’s about to go off the deep end, I suggest, and Adichie smiles to acknowledge how impossible she is.

From The Guardian • Mar. 4, 2017

"Haven't you ever wanted to go off the deep end and not care what anybody thinks?"

From Terminal Compromise: computer terrorism: when privacy and freedom are the victims: a novel by Schwartau, Winn

Related Words

• freak out
• go off
• lose it