over·​ac·​tive | \ˌō-vər-ˈak-tiv \

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 \ 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

These cellular cyborgs could one day step in when your body falls short in its attempts to hunt cancer cells, tamp down overactive immune responses or adjust the gut microbiome. Eric Smalley, Discover Magazine, "Cellular Cyborgs: How Programmable DNA Strands Might Control Healing," 25 Sep. 2018 While an underactive thyroid can cause weight gain, an overactive one (which is diagnosed as hyperthyroidism) increases your metabolism, which can in turn cause increased hunger, Gilwit says. Colleen Stinchcombe, Woman's Day, "Why Am I Always Hungry?," 19 Oct. 2018 Drew disappears for a while, as attention turns to Dax, an overactive and undersized coach trying to put together a Rucker team. Mark Feeney, BostonGlobe.com, "In ‘Uncle Drew,’ Kyrie dribbles, Kyrie shoots, Kyrie acts," 27 June 2018 There are also non-steroidal creams that work by tamping down on your overactive immune system or suppressing inflammation. Korin Miller, SELF, "Here’s Exactly What to Do About Eczema on Your Eyelid," 3 July 2018 Animal studies had shown that overactive cells on that pathway would release pain signals and cause migraine symptoms. David Noonan, Scientific American, "New Nerve Drugs May Finally Prevent Migraine Headaches," 1 Dec. 2015 Sometimes, Van Ness’s overactive, hot-wired brain causes the podcast to veer unabashedly off the rails. refinery29.com, "The Jonathan Van Ness Podcast You Need In Your Life, Henny," 14 June 2018 An overactive appetite is a job requirement, right? Nestor Ramos, BostonGlobe.com, "Will my genes doom my young daughter to a weight problem?," 31 Jan. 2018 In the naturally resilient animals the higher neural activity seemed to induce a counterreaction that resulted in the subsequent quieting of overactive neurons. Gary Stix, Scientific American, "Can a Pill that Boosts ‘Resilience’ Treat Depression?," 11 Apr. 2018

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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Last Updated

30 Nov 2018

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Time Traveler for overactive

The first known use of overactive was in 1647

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More Definitions for overactive



English Language Learners Definition of overactive

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


over·​ac·​tive | \ˌō-və-ˈrak-tiv \

Medical Definition of overactive 

: excessively or abnormally active an overactive mind overactive glands

Other Words from overactive

overactivity \-​ˌrak-​ˈtiv-​ət-​ē \ noun plural overactivities

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More from Merriam-Webster on overactive

Rhyming Dictionary: Words that rhyme with overactive

Thesaurus: All synonyms and antonyms for overactive

Spanish Central: Translation of overactive

Nglish: Translation of overactive for Spanish Speakers

Comments on overactive

What made you want to look up overactive? Please tell us where you read or heard it (including the quote, if possible).


to move with a clumsy heavy tread

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