di·​ag·​no·​sis | \ ˌdī-ig-ˈnō-səs How to pronounce diagnosis (audio) , -əg- \
plural diagnoses\ ˌdī-​ig-​ˈnō-​ˌsēz How to pronounce diagnosis (audio) , -​əg-​ \

Definition of diagnosis

1a : the art or act of identifying a disease from its signs and symptoms
b : the decision reached by diagnosis the doctor's diagnosis
2a : investigation or analysis of the cause or nature of a condition, situation, or problem diagnosis of engine trouble
b : a statement or conclusion from such an analysis
3 biology : a concise technical description of a taxon

Examples of diagnosis in a Sentence

The unusual combination of symptoms made accurate diagnosis difficult. She is an expert in the diagnosis and treatment of eye diseases. The diagnosis was a mild concussion. His doctor made an initial diagnosis of pneumonia. The committee published its diagnosis of the problems affecting urban schools.
Recent Examples on the Web But in a busy hospital, prompt sepsis diagnosis can be difficult. Sophie Bushwick, Scientific American, 1 Aug. 2022 Any delays to an accurate diagnosis can allow the bacterium to cause more severe disease. Beth Mole, Ars Technica, 28 July 2022 Typical acne remedies are often ineffective against Pityrosporum folliculitis, which makes a proper diagnosis vital. Tatjana Freund, ELLE, 27 July 2022 Casey Wilson is sharing how her son's celiac diagnosis has impacted her own perspective on health and wellness. Glenn Garner, PEOPLE.com, 26 July 2022 Murkowski’s positive test follows U.S. President Joe Biden’s COVID-19 diagnosis last week. Riley Rogerson, Anchorage Daily News, 26 July 2022 This sounds as if every medical diagnosis will have to be made with an accompanying political and sociological analysis. The Editorial Board, WSJ, 26 July 2022 Kushner's cancer diagnosis had never been revealed prior to this book. Brendan Morrow, The Week, 26 July 2022 The other programs spent much of the time addressing the latest Jan. 6 hearing developments as well as other headlines like President Biden's COVID diagnosis. Fox News, 25 July 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'diagnosis.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of diagnosis

1634, in the meaning defined at sense 1a

History and Etymology for diagnosis

New Latin, from Greek diagnōsis, from diagignōskein to distinguish, from dia- + gignōskein to know — more at know

Learn More About diagnosis

Time Traveler for diagnosis

Time Traveler

The first known use of diagnosis was in 1634

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Dictionary Entries Near diagnosis



diagnosis related group

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Statistics for diagnosis

Last Updated

5 Aug 2022

Cite this Entry

“Diagnosis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diagnosis. Accessed 10 Aug. 2022.

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More Definitions for diagnosis


di·​ag·​no·​sis | \ ˌdī-əg-ˈnō-səs How to pronounce diagnosis (audio) \
plural diagnoses\ -​ˌsēz \

Kids Definition of diagnosis

1 : the act of recognizing a disease from its signs and symptoms She specialized in the diagnosis and treatment of eye diseases.
2 : the conclusion that is reached following examination and testing The diagnosis was pneumonia.


di·​ag·​no·​sis | \ ˌdī-ig-ˈnō-səs, -əg- How to pronounce diagnosis (audio) \
plural diagnoses\ -​ˌsēz How to pronounce diagnosis (audio) \

Medical Definition of diagnosis

1a : the art or act of identifying a disease from its signs and symptoms
b : the decision reached by diagnosis a diagnosis of pneumonia
2 : a concise technical description of a taxon

More from Merriam-Webster on diagnosis

Nglish: Translation of diagnosis for Spanish Speakers

Britannica English: Translation of diagnosis for Arabic Speakers

Britannica.com: Encyclopedia article about diagnosis


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