underactive

adjective un·der·ac·tive \-ˈak-tiv\

: not active enough

Full Definition of UNDERACTIVE

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

— un·der·ac·tiv·i·ty \-ˈti-və-tē\ noun

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1959

Medical Dictionary

adjective un·der·ac·tive \-ˈak-tiv\

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

—un·der·ac·tiv·i·ty \-ak-ˈtiv-ət-ē\ noun, plural un·der·ac·tiv·i·ties

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