over·​re·​act ˌō-vər-rē-ˈakt How to pronounce overreact (audio)
overreacted; overreacting

intransitive verb

: to react to something too strongly : to respond to something with too strong an emotion or with unnecessary or excessive action
I was furious and yelled at him. He told me I was overreacting and to "chillax."Ben Stein
The world isn't coming to an end. You shouldn't overreact to the negative news.Adam Bryant
Some of his animals had become apprehensive and twitchy, overreacting to sound or touch …Mark Caldwell
But the military police overreacted, using tear gas, rubber bullets and excessive force in front of news cameras that spread the images countrywide.Grant Wahl
… the poisonous surfeit of hormones produced by the overreacting immune system.Shannon Brownlee
Sometimes companies in a little bit of trouble are the best investments because the market has overreacted.Orson C. Clay
overreaction noun
plural overreactions
… he had said almost angrily that he couldn't tell her anything without eliciting a huge overreaction. Ann Beattie
This response is an overreaction by your immune system to an otherwise harmless substance, such as pollen or pet dander. Medical Clinic Health Letter

Word History

First Known Use

1919, in the meaning defined above

Time Traveler
The first known use of overreact was in 1919

Dictionary Entries Near overreact

Cite this Entry

“Overreact.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/overreact. Accessed 8 Feb. 2023.

Medical Definition


intransitive verb
over·​re·​act ˌō-və(r)-rē-ˈakt How to pronounce overreact (audio)
: to react excessively or too strongly
the body's immune system overreacts to the endotoxinTina Adler
overreaction noun

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