underactive

American  

[uhn-der-ak-tiv] / ˌʌn dərˈæk tɪv /

adjective

1. insufficiently active.

   an underactive thyroid gland.

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underactive British  

/ ˌʌndərˈæktɪv /

adjective

1. (of the thyroid or adrenal glands) not functioning at full capacity

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Other Word Forms

• underactiveness noun
• underactivity noun

Etymology

Origin of underactive

First recorded in 1955–60; under- + active

Example Sentences

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.

From Salon

Laura is 41 and has Down's syndrome, asthma and an underactive thyroid.

From BBC

Following the treatment, Eleanore has lost a significant amount of her eyesight, while she has an underactive thyroid and adrenal insufficiency.

From BBC

"Mental illness is described as overactive emotion circuits and underactive cognitive control circuits. That's how almost every single mental illness is described."

From Salon

Of oral drugs to treat underactive thyroid, 66 percent contain lactose.

From Washington Post