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 gift was made in memory of Conte’s father, Pierre Conte, who was diagnosed with Parkinson’s disease in his 70s and passed away in 2017, and underscores Conte’s strategic approach to philanthropy. Jason Phillips, USA Today, 17 June 2025 After his release in 2018, doctors diagnosed him with moderate cerebral edema and a broken nose that required surgery. Verónica Egui Brito, Miami Herald, 17 June 2025 During the second emergency room visit, V.T. was diagnosed with CHS. Passport: Explore the finest destinations and experiences around the world in the Forbes Passport newsletter. Dario Sabaghi, Forbes.com, 17 June 2025 Then, in 2020, she was diagnosed with metastatic ovarian cancer. Siddhartha Mukherjee, New Yorker, 16 June 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 26 Jun. 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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