underactive
adjective
un·der·ac·tive
ˌən-dər-ˈak-tiv 
: characterized by an abnormally low level of activity
an underactive thyroid gland
Examples of underactive in a Sentence
Recent Examples on the Web
Phytochemicals can help support balanced immune function (neither underactive nor overactive).
—
Heather Jones, Verywell Health, 21 Feb. 2025
Hypothyroidism, or underactive thyroid, occurs when the thyroid gland doesn't produce enough hormones.
—Merve Ceylan, Health, 25 Jan. 2025
Interpreting Your Results Low or high TSH levels may indicate a thyroid disorder (overactive or underactive).
—Brandi Jones, Msn-Ed, Rn-Bc, Health, 6 Dec. 2024
Thyroid Medication Thyroid medications like Synthroid (levothyroxine) and Armour Thyroid are used to treat underactive thyroid (hypothyroidism).
—Alex Yampolsky, Verywell Health, 28 Oct. 2024
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Heather Jones, Verywell Health, 21 Feb. 2025
Hypothyroidism, or underactive thyroid, occurs when the thyroid gland doesn't produce enough hormones.
—Merve Ceylan, Health, 25 Jan. 2025
Interpreting Your Results Low or high TSH levels may indicate a thyroid disorder (overactive or underactive).
—Brandi Jones, Msn-Ed, Rn-Bc, Health, 6 Dec. 2024
Thyroid Medication Thyroid medications like Synthroid (levothyroxine) and Armour Thyroid are used to treat underactive thyroid (hypothyroidism).
—Alex Yampolsky, Verywell Health, 28 Oct. 2024
See All Example Sentences for underactive
Cite this Entry
“Underactive.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/underactive. Accessed 20 May. 2025.
Copy CitationKids Definition
underactive
adjective
un·der·ac·tive
ˌən-də-ˈrak-tiv
: having an abnormally low level of activity
an underactive gland
Medical Definition
underactive
adjective
un·der·ac·tive
-ˈak-tiv
: characterized by an abnormally low level of activity
an underactive thyroid gland
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