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.
In many vertebrates, overactive NRF2 triggers big problems like tumor growth. Lauren Leffer, Popular Science, 27 Mar. 2025 The goldfish exercise helps relax overactive jaw muscles, reduces joint strain, and improves maximal mouth opening by reducing tightness in the temporomandibular joint.4 3. Christopher Bergland, Verywell Health, 21 Mar. 2025 Integrative Medicine In Autoimmune Disorders Autoimmune diseases—including lupus, rheumatoid arthritis, Hashimoto’s thyroiditis, and multiple sclerosis—result from an overactive immune system attacking the body's own tissues. Jesse Pines, Forbes, 12 Mar. 2025 In lupus, chemotherapy drugs suppress the overactive immune system, helping to reduce inflammation, limit organ damage, and improve quality of life. David Faris, Newsweek, 27 Feb. 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 31 Mar. 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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