major depressive disorder
noun
: a serious mood disorder involving one or more episodes of intense psychological depression or loss of interest or pleasure that lasts two or more weeks and is accompanied by irritability, fatigue, poor concentration, sleep disturbances, weight gain or loss, feelings of worthlessness or guilt, and sometimes suicidal tendencies : clinical depression, major depression
About 18 million Americans are diagnosed with a major depressive disorder each year.—
David Schwab
David SchwabThe most serious form of depression is major depressive disorder, characterized by depressed mood, loss of interest or pleasure, changes in appetite, increased or decreased sleep, increased or decreased motor activity, fatigue, feelings of worthlessness or guilt, difficulty concentrating and, for some people, recurrent thoughts of death or suicide.—Sandi Lloyd
—abbreviation MDD
Sandi LloydExamples of major depressive disorder in a Sentence
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UConn Today reported that between 11.1% and 14.7% of ADRD cases affecting roughly one million people in the United States are attributable to major depressive disorder.
—Livi Stanford, Hartford Courant, 29 July 2025
However, those who used dating apps frequently were more likely to have symptoms of major depressive disorders.
—Kara Alaimo, CNN Money, 25 July 2025
The initial 2020 trial, published in JAMA Psychiatry, included 24 patients with major depressive disorder.
—Khloe Quill, FOXNews.com, 24 June 2025
It has since been approved for migraines, anxious depression and major depressive disorder.
—Nicole Villalpando, Austin American Statesman, 30 July 2025
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Livi Stanford, Hartford Courant, 29 July 2025
However, those who used dating apps frequently were more likely to have symptoms of major depressive disorders.
—Kara Alaimo, CNN Money, 25 July 2025
The initial 2020 trial, published in JAMA Psychiatry, included 24 patients with major depressive disorder.
—Khloe Quill, FOXNews.com, 24 June 2025
It has since been approved for migraines, anxious depression and major depressive disorder.
—Nicole Villalpando, Austin American Statesman, 30 July 2025
See All Example Sentences for major depressive disorder
Cite this Entry
“Major depressive disorder.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/major%20depressive%20disorder. Accessed 21 Aug. 2025.
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major depressive disorder
noun
: a serious mood disorder involving one or more episodes of intense psychological depression or loss of interest or pleasure that lasts two or more weeks and is accompanied by irritability, fatigue, poor concentration, sleep disturbances, weight gain or loss, feelings of worthlessness or guilt, and sometimes suicidal tendencies : clinical depression, major depression
The diagnosis of both major depressive disorder and subsyndromal symptoms is complicated by difficulties that elderly patients may have in recognizing or describing depressive symptoms.—Lawrence M. Martin et al., The John Hopkins White Papers
—abbreviation MDD
Lawrence M. Martin et al., The John Hopkins White PapersLove words? Need even more definitions?
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