overactive

adjective

over·​ac·​tive ˌō-vər-ˈak-tiv How to pronounce overactive (audio)
: excessively or abnormally active
overactive glands
an overactive imagination
overactivity 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Your overactive immune response can lead to inflammation and congestion, among other symptoms. Lindsay Curtis, Health, 25 Apr. 2025 So, Gemini can relate to the stress and lack of rest that Victoria goes through since the twin star has an overactive mind. Lisa Stardust, People.com, 21 Mar. 2025 For chronic pain sufferers like me, the pain pathways in our brains often become overactive. Peter Ubel, Forbes, 25 Feb. 2025 Systemic medications, which impact the whole body and can be more effective than other treatments in tougher eczema cases, work internally to calm the overactive immune response that often drives the condition. Lynya Floyd, Allure, 23 May 2025 See All Example Sentences for overactive

Word History

First Known Use

1647, in the meaning defined above

Time Traveler
The first known use of overactive was in 1647

Browse Nearby Words

Cite this Entry

“Overactive.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/overactive. Accessed 10 Jun. 2025.

Kids Definition

overactive

adjective
over·​ac·​tive ˌō-və-ˈrak-tiv How to pronounce overactive (audio)
: very active and especially abnormally so
an overactive thyroid
overactivity noun

Medical Definition

overactive

adjective
over·​ac·​tive ˌō-və-ˈrak-tiv How to pronounce overactive (audio)
: excessively or abnormally active
an overactive mind
overactive glands
overactivity noun
plural overactivities

More from Merriam-Webster on overactive

Last Updated: - Updated example sentences
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