underactive

adjective

un·​der·​ac·​tive ˌən-dər-ˈak-tiv How to pronounce underactive (audio)
: characterized by an abnormally low level of activity
an underactive thyroid gland
underactivity noun

Examples of underactive in a Sentence

Recent Examples on the Web Based on a physical examination, other symptoms and medical history, the health practitioner suspects that the patient could be suffering from any of the following: anemia, an underactive thyroid or diabetes. Brad Reisfeld, Discover Magazine, 12 Feb. 2024 An underactive or overactive thyroid gland can cause your period to come twice in one month. Women's Health, 23 Aug. 2023 For example, the same circuit may be overactive in someone with depression post-TBI and underactive in someone with depression and no TBI. Kaitlin Sullivan, NBC News, 5 July 2023 Some people with an underactive thyroid (hypothyroidism) may have swelling around their eyes. Amanda Gardner, Health, 28 Nov. 2023 The opposite is true for those who don't make enough thyroid hormone and have an underactive thyroid. Kiera Aaron, Health, 31 Oct. 2023 An underactive thyroid may cause your face to get puffy. Lisa Mulcahy, Men's Health, 29 Aug. 2023 More prevalent in women, it’s also known as chronic lymphocytic thyroiditis, and is the most common cause of underactive thyroid in the U.S. Having another autoimmune disorder can put someone at elevated risk of developing Hashimoto’s. Isabella Cueto, STAT, 18 Aug. 2023 Too much iodine might cause an underactive or overactive thyroid. Erica Sweeney, Men's Health, 22 June 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'underactive.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1959, in the meaning defined above

Time Traveler
The first known use of underactive was in 1959

Dictionary Entries Near underactive

Cite this Entry

“Underactive.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/underactive. Accessed 29 Mar. 2024.

Kids Definition

underactive

adjective
un·​der·​ac·​tive ˌən-də-ˈrak-tiv How to pronounce underactive (audio)
: having an abnormally low level of activity
an underactive gland

Medical Definition

underactive

adjective
un·​der·​ac·​tive -ˈak-tiv How to pronounce underactive (audio)
: characterized by an abnormally low level of activity
an underactive thyroid gland
underactivity noun
plural underactivities
Last Updated: - Updated example sentences
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