di·​ag·​nose | \ ˈdī-ig-ˌnōs , -ˌnōz, ˌdī-ig-ˈ, -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 , -​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

In a heartfelt Instagram post, Selma Blair revealed that she was diagnosed with multiple sclerosis. Ilana Kaplan, Allure, "Selma Blair Reveals She Has Multiple Sclerosis in Heartfelt Post," 22 Oct. 2018 After he was diagnosed with depression, Jared launched a T-shirt campaign with represent.com that benefits the mental illness support organization To Write Love On Her Arms. Brittney Mcnamara, Teen Vogue, "12 Celebrities Who Talk About Mental Health," 10 Oct. 2018 An Iowa couple who welcomed their first baby in July had been preparing to say goodbye to him since about halfway through their pregnancy after doctors diagnosed the unborn child with a terminal brain malformation. Alexandria Hein, Fox News, "Parents of baby misdiagnosed with terminal brain condition in utero left fate 'in God's hands'," 28 Aug. 2018 The two-hour movie breezes through the life of the late comic, who died of suicide in 2014 at age 63, months after he was diagnosed with Parkinson's Disease. Patrick Ryan, USA TODAY, "HBO's Robin Williams film explores late comic's life, 'extremely difficult' final months," 13 July 2018 Everyone at Dundee Football Club are devastated to learn that club legend Alan Gilzean passed away this morning after recently being diagnosed with a brain tumour. SI.com, "Tottenham Hotspur Release Statement as Club Legend Alan Gilzean Passes Away at 79," 8 July 2018 The school notified the state Division of Public Health Services on June 1 after a student was diagnosed with whooping cough. Portsmouth Herald, BostonGlobe.com, "Officials confirm whooping cough outbreak at N.H. high school," 19 June 2018 Volunteer Teresa Mittons’ love of food came from cooking with her father after he was diagnosed with early onset Alzheimer’s disease. Hannah Steinkopf-frank, RedEye Chicago, "Chicago in action: Give back to the city with these three volunteer organizations," 14 June 2018 As Emmy underwent surgery, Mom clutched a tattered yellow stuffed animal named Ducky, who was given to Emmy after she was diagnosed with diabetes. Wayne Drash, CNN, "The medicine keeping her alive was also killing her," 12 June 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

21 Feb 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 \
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 , -ˌnōz , 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-​ \ 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

Comments on diagnose

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excited commotion or publicity

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