overactive
adjective
over·ac·tive
ˌō-vər-ˈak-tiv 
: excessively or abnormally active
overactive glands
an overactive imagination
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
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
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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
Cite this Entry
“Overactive.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/overactive. Accessed 31 Mar. 2025.
Copy CitationKids Definition
overactive
adjective
over·ac·tive
ˌō-və-ˈrak-tiv
: very active and especially abnormally so
an overactive thyroid
Medical Definition
overactive
adjective
over·ac·tive
ˌō-və-ˈrak-tiv
: excessively or abnormally active
an overactive mind
overactive glands
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