di·​ag·​nose | \ ˈdī-ig-ˌnōs How to pronounce diagnose (audio) , -ˌnōz, ˌdī-ig-ˈnōs How to pronounce diagnose (audio) , -ˈnōz, -əg-\
diagnosed; diagnosing

Definition of diagnose

transitive verb

1a : to recognize (something, such as a disease) by signs and symptoms The other method of diagnosing gallstones is through an ultrasound examination, which has the advantages of being simple, safe and quick.— G. Timothy Johnson Pulmonary embolus was diagnosed in two of the actively treated patients …— Richard D. Sautter et al.
b : to recognize a disease or condition in The physicist and cosmologist was diagnosed with Lou Gehrig's disease when he was a 21-year-old student at Cambridge University.— Maria Cheng
2 : to analyze the cause or nature of The mechanic diagnosed the problem with the engine.

intransitive verb

: to identify a disease from its signs and symptoms : to make a diagnosis

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Other Words from diagnose

diagnosable or diagnoseable \ ˌdī-​ig-​ˈnō-​sə-​bəl How to pronounce diagnoseable (audio) , -​əg-​ , -​zə-​ \ adjective

Examples of diagnose in a Sentence

The test is used to help in diagnosing heart disease. Thousands of new cases have been diagnosed in the past year. The doctor was unable to diagnose the skin condition. a new doctor with little experience diagnosing patients The mechanic was unable to diagnose the problem.
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Recent Examples on the Web

Officers placed the second person recently diagnosed with mumps in a medical isolation room as well. Sophie Carson, Milwaukee Journal Sentinel, "Two detainees at Kenosha County Detention Center diagnosed with mumps," 7 June 2019 People diagnosed with summer SAD have experienced these symptoms for at least two years. Shelby Deering, Good Housekeeping, "Summer Depression Is a Thing — Here’s What You Need to Know," 7 June 2019 When compared to people who don't have cancer, people diagnosed with anal cancer are about 67% as likely to live at least five years beyond their diagnosis. Michael Nedelman, CNN, "Actress shines light on HPV's link to anal cancers," 6 June 2019 Service members diagnosed with gender dysphoria before April 12, 2019, are exempt from the new policy and eligible for surgery. Grace Segers, CBS News, "Fact checking Trump's comments on transgender military service members," 5 June 2019 What about someone diagnosed with the schizophrenias? Anna Altman, The New Yorker, "In “The Collected Schizophrenias,” Esmé Weijun Wang Maps the Terrain of Her Mental Illness," 4 June 2019 Her graduate work focused on the use of prenatal exercise to promote cardiometabolic health in women diagnosed with, or at risk for, gestational diabetes. Get-fit Guy Brock Armstrong, Scientific American, "How Much Should You Exercise while Pregnant?," 25 May 2019 The increase in suicide attempts parallels a rise in Texas prisoners being diagnosed with mental health conditions, despite the overall prison population being on a decline. Jake Bleiberg, The Seattle Times, "Rise in suicide attempts in Texas prisons alarms advocates," 12 Apr. 2019 Costello said in diagnosing the problem for suburban voters. Dylan Scott, Vox, "The suburbs abandoned Republicans in 2018, and they might not be coming back.," 26 Dec. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'diagnose.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of diagnose

circa 1859, in the meaning defined at transitive sense 1

History and Etymology for diagnose

back-formation from diagnosis

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Statistics for diagnose

Last Updated

13 Jun 2019

Look-up Popularity

Time Traveler for diagnose

The first known use of diagnose was circa 1859

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More Definitions for diagnose



English Language Learners Definition of diagnose

: to recognize (a disease, illness, etc.) by examining someone
: to recognize a disease, illness, etc., in (someone)
: to find the cause of (a problem)


di·​ag·​nose | \ ˈdī-əg-ˌnōs How to pronounce diagnose (audio) \
diagnosed; diagnosing

Kids Definition of diagnose

: to recognize (as a disease) by signs and symptoms The test is used for diagnosing strep throat.


di·​ag·​nose | \ ˈdī-ig-ˌnōs How to pronounce diagnose (audio) , -ˌnōz How to pronounce diagnose (audio) , ˌdī-ig-ˈ, -əg-\
diagnosed; diagnosing

Medical Definition of diagnose

transitive verb

1 : to recognize (as a disease) by signs and symptoms
2 : to diagnose a disease or condition in diagnosed the patient

Other Words from diagnose

diagnosable also diagnoseable \ ˌdī-​ig-​ˈnō-​sə-​bəl, -​əg-​, -​zə-​ How to pronounce diagnoseable (audio) \ adjective

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More from Merriam-Webster on diagnose

Rhyming Dictionary: Words that rhyme with diagnose

Spanish Central: Translation of diagnose

Nglish: Translation of diagnose for Spanish Speakers

Britannica English: Translation of diagnose for Arabic Speakers

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