diagnostic

1 of 2

adjective

di·​ag·​nos·​tic ˌdī-ig-ˈnä-stik How to pronounce diagnostic (audio)
-əg-
variants or less commonly diagnostical
ˌdī-ig-ˈnä-sti-kəl How to pronounce diagnostic (audio)
-əg-
Synonyms of diagnosticnext
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
ˌdī-ig-ˈnä-sti-k(ə-)lē How to pronounce diagnostic (audio)
-əg-
adverb

diagnostic

2 of 2

noun

1
: the art or practice of diagnosis
—often plural
2
: a distinguishing mark
diagnostician
ˌdī-ig-(ˌ)nä-ˈsti-shən How to pronounce diagnostic (audio)
-əg-
noun

Synonyms of diagnostic

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Adjective

Noun

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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
This diagnostic shift moves management out of reactive fire-fighting and into intentional system design. — Natalie Grabher, Forbes.com, 1 Sep. 2026 Rates of autism are rising to previously unseen levels, owing largely to better detection and new diagnostic criteria, but the numbers are still disconcerting. — Ruby Cramer, New Yorker, 31 Aug. 2026
Noun
Seo says the itineraries his company builds now front-load the diagnostics, usually a full checkup and a skin analysis in the first two days, with the rest of the trip customized around the results. — Christopher Elliott, Forbes.com, 29 Aug. 2026 Provide prenatal diagnostics, TeleNICU access, neonatal education, standardized care pathways, bridge-to-home services, and rural newborn care coordination. — Arkansas Democrat-Gazette, Arkansas Online, 27 Aug. 2026 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

Rhymes for diagnostic

See All Rhymes for diagnostic

Browse Nearby Words

diagnosis related group
diagnostic
diagnostically
See all Nearby Words

Cite this Entry

“Diagnostic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diagnostic. Accessed 4 Sep. 2026.

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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
-ti-kəl How to pronounce diagnostic (audio)
1
: of, relating to, or used in diagnosis
2
: using the methods of or yielding a diagnosis
a diagnostic service
diagnostic properties
diagnostically
-ti-k(ə-)lē How to pronounce diagnostic (audio)
adverb

diagnostic

2 of 2 noun
: the art or practice of diagnosis
—often used in plural
Last Updated: - Updated example sentences
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