over·​ac·​tive | \ ˌō-vər-ˈak-tiv How to pronounce overactive (audio) \

Definition of overactive

: excessively or abnormally active overactive glands an overactive imagination

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Other Words from overactive

overactivity \ ˌō-​vər-​ak-​ˈti-​və-​tē How to pronounce overactive (audio) \ noun

Examples of overactive in a Sentence

She has an overactive bladder. His crazy ideas are products of an overactive imagination.
Recent Examples on the Web One theory is that an overactive immune system can cause the release of histamine, similar to what happens when the body encounters an allergen. Allyson Chiu, Washington Post, "Covid may cause rashes and swelling. That doesn’t mean you’re ‘allergic,’ experts say.," 2 Dec. 2020 But not everyone with an overactive amygdala necessarily has BPD. Yasmin Lajoie, refinery29.com, "“Tomorrow I’ll Be Someone Else”: Living With Borderline Personality Disorder," 3 Sep. 2020 And that is why, in rare cases, children and others get so sick with what’s known as multisystem inflammatory syndrome, in which an overactive immune system harms the body in a friendly fire attack. Tom Frieden, WSJ, "How to Handle the Covid-19 Vaccine Breakthrough the Right Way," 4 Dec. 2020 But severe Covid-19 can involve a second phase in which a person’s immune system gets overactive and starts to damage the body. Adam Rogers, Wired, "President Donald Trump Tests Positive for Covid-19," 2 Oct. 2020 Administering dexamethasone or other steroids to help suppress the overactive inflammatory response in severely ill patients. Deborah Netburn, Los Angeles Times, "Coronavirus infections are higher than ever, but COVID-19 deaths are not. Why?," 25 Nov. 2020 Administering dexamethasone or other steroids to help suppress the overactive inflammatory response in severely ill patients. Author: Deborah Netburn, Anchorage Daily News, "Coronavirus infections are higher than ever, but COVID-19 death rates are not. Why?," 25 Nov. 2020 Also helpful are new medications, such as the antiviral drug remdesivir to slow the virus and the steroid dexamethasone to suppress an overactive immune system. Angie Leventis Lourgos, chicagotribune.com, "’No sign of slowing’: Illinois hospitalizations could soon break pandemic record, raising concerns about capacity," 6 Nov. 2020 Anchorage’s mayor has been overactive and destroyed the local economy, and school system while using covid relief money for his Agendas. Anchorage Daily News, "Candidate Q&A: Alaska House District 22 — David Nees," 3 Oct. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'overactive.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of overactive

1647, in the meaning defined above

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Time Traveler for overactive

Time Traveler

The first known use of overactive was in 1647

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Statistics for overactive

Last Updated

25 Dec 2020

Cite this Entry

“Overactive.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/overactive. Accessed 24 Jan. 2021.

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More Definitions for overactive


How to pronounce overactive (audio)

English Language Learners Definition of overactive

: too active especially in a way that produces a bad result


over·​ac·​tive | \ ˌō-və-ˈrak-tiv How to pronounce overactive (audio) \

Medical Definition of overactive

: excessively or abnormally active an overactive mind overactive glands

Other Words from overactive

overactivity \ -​ˌrak-​ˈtiv-​ət-​ē How to pronounce overactive (audio) \ noun, plural overactivities

More from Merriam-Webster on overactive

Thesaurus: All synonyms and antonyms for overactive

Nglish: Translation of overactive for Spanish Speakers

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