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 disease is most commonly diagnosed in middle-aged men.

b : to diagnose a disease or condition in diagnosed the patient

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

She has been diagnosed with bipolar and anxiety disorders. Heather Gillers, WSJ, "‘I Was Hoping to Be Retired’: The Cost of Supporting Parents and Adult Children," 16 Nov. 2018 Choquette, 54, had been diagnosed with multiple sclerosis in 2009 and given a prescription for gabapentin before he was imprisoned in 2011 for the murder of a Forks man that Choquette believed was physically abusing a female friend. Christine Clarridge, The Seattle Times, "Washington prison inmate awarded $549,000 after he’s denied pain medication for multiple sclerosis," 7 Nov. 2018 Norway's Crown Princess Mette-Marit has been diagnosed with chronic lung disease. Caroline Hallemann, Town & Country, "Crown Princess Mette-Marit of Norway Has Been Diagnosed With Lung Disease," 25 Oct. 2018 Almost exactly one year ago, Lady Gaga took to Twitter to share that she had been diagnosed with fibromyalgia, which caused chronic pain and eventually led to her postponing several of her fall 2017 European tour dates. Andrea Park, Allure, "Lady Gaga Opens Up in Vogue Interview About Struggling With Fibromyalgia and PTSD," 12 Sep. 2018 His wife was a huge fan of Fixer Upper, and she’d been diagnosed with terminal cancer. Sarah Weinberg, House Beautiful, "What It's like To Live in A Famous "Fixer Upper" House," 9 Aug. 2018 And Harriett’s husband, Hy — who’d made a fortune buying thousands of acres in south Orlando long before the boom years — had been diagnosed with Alzheimer’s. Scott Maxwell, OrlandoSentinel.com, "Harriett Lake: Orlando's grande dame of philanthropy was wry, witty and oh-so-generous," 11 July 2018 Those affected have been diagnosed with cyclosporiasis, an intestinal infection caused by the cyclospora parasite. Matthew Diebel, USA TODAY, "More than 200 hit by parasite from Del Monte vegetables; symptoms can include 'explosive' bowel movements," 9 July 2018 As an adult, she was also diagnosed with MS, but that has never stopped the 46-year-old athlete from pursuing her dreams. Eileen Reslen, Good Housekeeping, "'Dancing With the Stars' Contestant Danelle Umstead Gave the Most Moving Performance Last Night," 25 Sep. 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

28 Nov 2018

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

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