hy·​po·​thy·​roid·​ism | \ˌhī-pō-ˈthī-ˌrȯi-ˌdi-zəm \

Definition of hypothyroidism 

: deficient activity of the thyroid gland also : a resultant bodily condition characterized by lowered metabolic rate and general loss of vigor

Examples of hypothyroidism in a Sentence

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The dearth of either can indicate hypothyroidism, which the Pets section of WebMD.com says isn't life-threatening, but can effect quality of life if untreated. David J. Neal, miamiherald, "What got this dog food recalled might have caused thyroid problems in four pooches," 13 June 2018 Since your thyroid influences so many systems in your body, having hypothyroidism can make your period a beast. Claire Gillespie, SELF, "This Is When to See Your Doctor About Heavy Periods," 29 Mar. 2018 Iron can also interfere with medications, including some meant to treat hypothyroidism and Parkinson’s disease. Cassie Shortsleeve, SELF, "Do I Really Need to Take Prenatal Vitamins Before I’m Even Pregnant?," 19 Apr. 2018 Allergic skin disease is the most common primary cause but a slow thyroid (hypothyroidism) and other skin disorders are possible, too. Patty Khuly, miamiherald, "Dogs, cats often suffer common inflammatory ear condition | Miami Herald," 19 Apr. 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 While women are more likely to develop Graves' disease than men, a key risk factor is a family history of hyperthyroidism or hypothyroidism, including conditions like Hashimoto's disease. Caroline Picard, Good Housekeeping, "What Is Graves' Disease? Symptoms and Treatment Options to Know About," 26 Feb. 2018 Also known as chronic lymphocytic thyroiditis, the condition causes the immune system to attack the thyroid and is the most common cause of hypothyroidism in the United States. Amanda Arnold, The Cut, "Gigi Hadid Opens Up About Autoimmune Disease," 12 Feb. 2018 In addition, a pair of 2015 studies by British and Canadian researchers suggested a link between fluoride overexposure and hypothyroidism and attention deficit hyperactivity disorder. OregonLive.com, "Fluoride in water: When it helps vs. when it harms," 14 Dec. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'hypothyroidism.' 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 hypothyroidism

1905, in the meaning defined above

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The first known use of hypothyroidism was in 1905

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hy·​po·​thy·​roid·​ism | \-ˌiz-əm \

Medical Definition of hypothyroidism 

: deficient activity of the thyroid gland also : a resultant bodily condition characterized by lowered metabolic rate and general loss of vigor

More from Merriam-Webster on hypothyroidism

Britannica.com: Encyclopedia article about hypothyroidism

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