diagnostic

1 of 2

adjective

di·​ag·​nos·​tic ˌdī-ig-ˈnä-stik How to pronounce diagnostic (audio)
-əg-
variants or less commonly diagnostical
1
a
: of, relating to, or used in diagnosis
a diagnostic tool
b
: using the methods of or yielding a diagnosis
diagnostic tests
2
: serving to distinguish or identify
a diagnostic feature
diagnostically adverb

diagnostic

2 of 2

noun

1
: the art or practice of diagnosis
often used in plural
2
: a distinguishing mark
diagnostician noun

Examples of diagnostic in a Sentence

Adjective Ultrasound is now widely used as a diagnostic tool. One important diagnostic feature of this condition is a mild rash. Noun the thesis that moral decline is the infallible diagnostic of a decadent society
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.
Adjective
As part of this recognition, IDF President Peter Schwarz publicly announced the launch of a type 5 diabetes working group, designed to help define the diagnostic criteria and treatments for this form of the disease. Melissa Rudy, FOXNews.com, 30 Sep. 2025 The International Diabetes Federation disagrees, though, and launched a working group aimed at developing better diagnostic criteria and treatment guidelines for Type 5 diabetes. Jonathan Lambert, NPR, 29 Sep. 2025
Noun
These changes can cause pricing pressure on Danaher's diagnostics and life sciences businesses in China, which has been a troubled market for the company. Morgan Chittum, CNBC, 18 Sep. 2025 When understood and leveraged effectively, platforms can offer transformative potential for diagnostics, patient care and beyond. Dr. William Morice, Forbes.com, 18 Sep. 2025 See All Example Sentences for diagnostic

Word History

First Known Use

Adjective

1625, in the meaning defined at sense 1a

Noun

1625, in the meaning defined at sense 1

Time Traveler
The first known use of diagnostic was in 1625

Cite this Entry

“Diagnostic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diagnostic. Accessed 1 Oct. 2025.

Kids Definition

diagnostic

adjective
di·​ag·​nos·​tic
ˌdī-ig-ˈnäs-tik
: of, relating to, or used in diagnosis
a diagnostic test for heart disease

Medical Definition

diagnostic

1 of 2 adjective
di·​ag·​nos·​tic -ˈnäs-tik How to pronounce diagnostic (audio)
variants also diagnostical
1
: of, relating to, or used in diagnosis
2
: using the methods of or yielding a diagnosis
a diagnostic service
diagnostic properties
diagnostically adverb

diagnostic

2 of 2 noun
: the art or practice of diagnosis
often used in plural

More from Merriam-Webster on diagnostic

Last Updated: - Updated example sentences
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