diagnosis

noun

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-
1
a
: the art or act of identifying a disease from its signs and symptoms
b
: the decision reached by diagnosis
the doctor's diagnosis
2
a
: 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
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.
Since then, Fox and Pollan have shared joys — like welcoming their four now-adult children Sam, 36, twins Aquinnah and Schuyler, 30, and Esmé, 23 — and challenges, including Fox’s 1991 Parkinson’s disease diagnosis. Eric Andersson, PEOPLE, 11 Oct. 2025 Kate Middleton has had a long year after her cancer diagnosis and remission. Stylecaster Editors, StyleCaster, 11 Oct. 2025 Biden, 82, first disclosed his cancer diagnosis in May, revealing that the disease had spread to his bones. Samantha-Jo Roth, The Washington Examiner, 11 Oct. 2025 Someone going through a breakup might tell themselves that their problems are nothing compared with a friend’s cancer diagnosis. Reem Kassis, The Atlantic, 11 Oct. 2025 See All Example Sentences for diagnosis

Word History

Etymology

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

First Known Use

1634, in the meaning defined at sense 1a

Time Traveler
The first known use of diagnosis was in 1634

Browse Nearby Words

Cite this Entry

“Diagnosis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diagnosis. Accessed 18 Oct. 2025.

Kids Definition

diagnosis

noun
di·​ag·​no·​sis ˌdī-ig-ˈnō-səs How to pronounce diagnosis (audio)
plural diagnoses -ˈnō-ˌsēz How to pronounce diagnosis (audio)
1
a
: the art or act of identifying a disease from its signs and symptoms
b
: the decision reached by diagnosis
2
a
: a careful study of something especially to determine its nature or importance
b
: the conclusion reached after a study or examination

Medical Definition

diagnosis

noun
di·​ag·​no·​sis ˌdī-ig-ˈnō-səs, -əg- How to pronounce diagnosis (audio)
plural diagnoses -ˌsēz How to pronounce diagnosis (audio)
1
a
: 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

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!