un·​der·​ac·​tive | \ ˌən-dər-ˈak-tiv How to pronounce underactive (audio) \

Definition of underactive

: characterized by an abnormally low level of activity an underactive thyroid gland

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Other Words from underactive

underactivity \ ˌən-​dər-​ak-​ˈti-​və-​tē How to pronounce underactivity (audio) \ noun

Examples of underactive in a Sentence

Recent Examples on the Web

While an underactive thyroid can cause weight gain, an overactive one (which is diagnosed as hyperthyroidism) increases your metabolism, which can in turn cause increased hunger, Gilwit says. Colleen Stinchcombe, Woman's Day, "Why Am I Always Hungry?," 19 Oct. 2018 The suit says he was seen at the VA's urology clinic for neurogenic bladder, a common complication of multiple sclerosis that causes the bladder to become overactive or underactive. Andy Marso, kansascity, "VA inflated catheter in Missouri man's penis, causing bleeding then death, suit says," 4 June 2018 Thyroid problems: Excessive hair loss, or telogen effluvium, can be a sign that your thyroid gland is overactive (hyperthyroidism) or underactive (hypothyroidism). Meghan Overdeep, Southern Living, "WATCH: What Your Hair Is Trying to Tell You About Your Health," 29 Mar. 2018 An underactive thyroid gland is usually treated with synthetic levothyroxine (Synthroid, Levothroid, Levoxyl). Teresa Graedon, The Seattle Times, "Black pepper is rich in benefits," 25 Feb. 2018 DeBonis said her cancer was found when her endocrinologist, who has treated her for an underactive thyroid for many years, decided to perform an ultrasound. Liz Szabo, Kaiser Health News, "Some Thyroid Cancer Patients Can Safely Delay Surgery," 31 Aug. 2017 Because the DLPFC is known to connect extensively to deeper brain areas that imaging studies have shown to be underactive in people addicted to cocaine, the trial aims to stimulate the region. Meredith Wadman, Science | AAAS, "Brain-altering magnetic pulses could zap cocaine addiction," 29 Aug. 2017 An overactive or underactive thyroid may cause hair loss and dry strands. Consumer Reports, Washington Post, "Little evidence for supplements to treat thinning hair, dry skin and brittle nails," 7 Aug. 2017 Someone with an undersize or underactive amygdala may not be able to feel empathy or refrain from violence. Barbara Bradley Hagerty, The Atlantic, "When Your Child Is a Psychopath," 16 May 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'underactive.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of underactive

1959, in the meaning defined above

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Time Traveler for underactive

The first known use of underactive was in 1959

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More Definitions for underactive



English Language Learners Definition of underactive

: not active enough


un·​der·​ac·​tive | \ -ˈak-tiv How to pronounce underactive (audio) \

Medical Definition of underactive

: characterized by an abnormally low level of activity an underactive thyroid gland

Other Words from underactive

underactivity \ -​ak-​ˈtiv-​ət-​ē How to pronounce underactivity (audio) \ noun, plural underactivities

Comments on underactive

What made you want to look up underactive? Please tell us where you read or heard it (including the quote, if possible).


to move or proceed with twists and turns

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