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.
This overactive immune system speeds up skin cell growth. Taylor Lane, Flow Space, 20 Nov. 2024 The effect was the same as that of an overactive group chat, if it were populated by pop stars instead of friends. Alex Barasch, The New Yorker, 7 Oct. 2024 Autoimmune diseases are characterized by overactive T and B immune cells. Amy Brownstein, Ms, Rdn, Verywell Health, 10 July 2024 An overactive thyroid can speed up heart rate and cause irregular heart rhythms. Alexandria Nyembwe, Phd, Rn, Health, 4 Nov. 2024 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

Dictionary Entries Near overactive

Cite this Entry

“Overactive.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/overactive. Accessed 4 Dec. 2024.

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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