diagnose

verb

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

transitive verb

1
a
: 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
diagnosable adjective
or diagnoseable

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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The only sign of emotion from him at sentencing came when the judge mentioned one of his daughters, who was in the process of being diagnosed with a life-changing medical condition. Simon Hughes, New York Times, 11 July 2025 The film’s superstitious heroine, AP (Sriram), is having her fortune told by a psychic in flowing robes and a matching huge headpiece (a delicious cameo from Big Freedia), who diagnoses the curse and the $1,000 solution to reverse it. Murtada Elfadl, Variety, 11 July 2025 Yungblud is postponing his Liverpool show due to being diagnosed with tonsillitis The musician was set to perform at The Dome in Liverpool on Friday, July 11 Fans were given free drinks as compensation Yungblud is postponing his show for health reasons — but leaving fans with a gift. Gabrielle Rockson, People.com, 11 July 2025 Duties can range from diagnosing and treat mental health issues to planning treatment programs and supervising staff who help provide care. Sacbee.com, 11 July 2025 See All Example Sentences for diagnose

Word History

Etymology

back-formation from diagnosis

First Known Use

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

Time Traveler
The first known use of diagnose was circa 1841

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Cite this Entry

“Diagnose.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diagnose. Accessed 14 Jul. 2025.

Kids Definition

diagnose

verb
di·​ag·​nose ˈdī-ig-ˌnōs How to pronounce diagnose (audio) -ˌnōz How to pronounce diagnose (audio)
ˌdī-ig-ˈnōs,
-ˈnōz
diagnosed; diagnosing
: to recognize by signs and symptoms : make a diagnosis
diagnose a disease
diagnose a play in football

Medical Definition

diagnose

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

transitive verb

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

More from Merriam-Webster on diagnose

Last Updated: - Updated example sentences
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