Definition of underactive
: characterized by an abnormally low level of activity an underactive thyroid gland
underactivityplay \ˌən-dər-ak-ˈti-və-tē\ noun
Recent Examples of underactive from the Web
The condition involves an underactive thyroid that can lead to weight gain and fatigue.
Someone with an undersize or underactive amygdala may not be able to feel empathy or refrain from violence.
The authors were researching the effectiveness of a drug that is widely, if controversially, used to treat older adults with subclinical hypothyroidism, better known as a slightly underactive thyroid.
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.
First Known Use of underactive
UNDERACTIVE Defined for English Language Learners
Definition of underactive for English Language Learners
: not active enough
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