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Related to underactive: underactive bladder, Underactive thyroid


Characterized by insufficient or abnormally low activity: an underactive area of the brain.

un′der·ac·tiv′i·ty (-ĭ-tē) n.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


1. not sufficiently active
2. (Medicine) med (of the thyroid or adrenal glands) not functioning at full capacity
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˌʌn dərˈæk tɪv)

insufficiently active: an underactive thyroid gland.
un`der•ac•tiv′i•ty, n.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adj.1.underactive - abnormally inactiveunderactive - abnormally inactive      
inactive - not active physically or mentally; "illness forced him to live an inactive life"; "dreamy and inactive by nature"
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
Over or underactive systems can lead to mental health problems
An alert against the homeopathic drug products Neuroveen, a natural relief of neuralgia nerve pain; Respitrol for safe, temporary relief of chest tightness, shortness of breath, wheezing and coughing; Thyroveev, a homeopathic remedy for underactive thyroid or hypothyroidism; and Compulsin, a natural relief of obsessive thoughts and compulsive urges, was issued by Dr.
Sensitivity to the cold There can be genetic links but an underactive thyroid is often caused by the immune system attacking and damaging the thyroid gland.
However, about 50 percent go undiagnosed, usually because they are symptom-free, and because many of the symptoms of hypothyroidism (underactive gland) and hyperthyroidism (overactive gland) can be mistaken for normal changes that occur with aging.
Depression, type 2 diabetes, and obesity--which raises the risk for heart problems, arthritis, and cancer--are also more common in people with an underactive thyroid.
People with an underactive thyroid gland produce insufficient amounts of the hormones required for optimal body functioning.
"Light exercise could help, but it's worth getting tests for anaemia or an underactive thyroid gland
With digestion either stirred by an overactive thyroid, or decelerating from an underactive one, our bowels act accordingly - either leading to an IBS-like state of recurrent bowel movements and diarrhoea or the opposite, constipation.
But swelling and stiffness can be caused by other more serious issues, such as an underactive thyroid and rheumatoid arthritis, and so should be checked by your doctor if you're concerned.