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

Other Words from diagnose

diagnosable or diagnoseable \ ˌdī-​ig-​ˈnō-​sə-​bəl How to pronounce diagnose (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.
Recent Examples on the Web The diagnosis is made clinically: There are no definitive blood tests, X-ray findings or genetic tests that reliably diagnose hEDS. Dr. Keith Roach, oregonlive, 27 Sep. 2022 Even as evidence of the plague became incontrovertible, doctors continued to diagnose alternate illnesses and peddle quack remedies. Sam Sacks, WSJ, 23 Sep. 2022 Stroud’s ability to process and diagnose have always been his greatest assets. Nathan Baird, cleveland, 7 Sep. 2022 Social workers can help children and their families address issues like poverty and domestic violence, and psychologists can evaluate and diagnose children. Paloma Esquivelstaff Writer, Los Angeles Times, 1 Sep. 2022 In May, the company expanded its access to digital tools to diagnose and make calibrations. Clarisa Diaz, Quartz, 25 Aug. 2022 In 2019, DeepMind unveiled a prototype for an A.I. program that can diagnose several eye diseases in approximately 30 seconds using its machine learning algorithm and a trove of relevant data. Tristan Bove, Fortune, 2 Sep. 2022 Over the past year, there has been a rapid expansion in the availability of at-home tests to diagnose Covid-19. Matthew Binnicker, Forbes, 8 Aug. 2022 The truth is, to diagnose most plant diseases, a scientist needs to culture plant tissue to correctly identify pathogens. Nick Goltz, The Conversation, 16 Aug. 2022 See More

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.

First Known Use of diagnose

circa 1841, in the meaning defined at transitive sense 1a

History and Etymology for diagnose

back-formation from diagnosis

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Time Traveler for diagnose

Time Traveler

The first known use of diagnose was circa 1841

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Statistics for diagnose

Last Updated

3 Oct 2022

Cite this Entry

“Diagnose.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diagnose. Accessed 4 Oct. 2022.

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More Definitions for diagnose


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 diagnose (audio) \ adjective


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