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-​ \

Definition of diagnostic

 (Entry 1 of 2)

1a : 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



Definition of diagnostic (Entry 2 of 2)

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

Other Words from diagnostic


diagnostically \ ˌdī-​ig-​ˈnä-​sti-​k(ə-​)lē How to pronounce diagnostic (audio) , -​əg-​ \ adverb


diagnostician \ ˌdī-​ig-​(ˌ)nä-​ˈsti-​shən How to pronounce diagnostic (audio) , -​əg-​ \ 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: Adjective Its sophisticated manufacturing facilities are so sensitive to every disruption, as everything from key raw materials such as chemicals to spare parts and diagnostic software depends on fragile cross-border supply chains. Christiaan Hetzner, Fortune, 2 Aug. 2022 Notably, the diagnostic business is poised for a mid-single or higher digit revenue growth in the coming years, as the division’s global addressable market is poised to grow at a CAGR of ~10% from +$150 billion in 2022 to ~$250 billion by 2026E. Joe Cornell, Forbes, 2 Aug. 2022 But giving a doctor the chance to assess family interactions in real-life settings, not the confines of a psychiatrist’s office, has diagnostic advantages, experts say. New York Times, 29 July 2022 Some laboratories and diagnostic companies have laid off employees or reassigned them to other tasks. Brianna Abbott, WSJ, 24 July 2022 And that could lead to delayed diagnostic and treatment services for patients, the brief says. Kate Brumback, ajc, 16 July 2022 But excess caution remains a problem, and has once again left the country dangerously short of diagnostic capacity. Benjamin Mazer, The Atlantic, 21 July 2022 The startup is working on expanding its diagnostic capabilities to include gum disease and joint abnormalities. John Kang, Forbes, 19 July 2022 Rittenband ordered him to Chino State Prison for a 90-day diagnostic examination before sentencing him. Gene Maddaus, Variety, 18 July 2022 Recent Examples on the Web: Noun The current gold-standard diagnostic for Lyme disease misses up to 60 percent of early-stage cases, according to the Bay Area Lyme Foundation. San Diego Union-Tribune, 8 Apr. 2022 The time lag between taking a COVID test and getting the result is a critical factor in evaluating any diagnostic. Anthony Warmack, Scientific American, 28 Mar. 2022 Tests such as the Abbott BinaxNOW, for example, were first studied as a rapid diagnostic that people could take shortly after their symptoms first appeared. Katherine J. Wu, The Atlantic, 23 Nov. 2021 One approach is ChangeShaper, Dare’s proprietary diagnostic and their partner, GCM’s ‘who is your business’ framework. Benjamin Laker, Forbes, 6 Oct. 2021 Silent, asymptomatic breakthroughs—those that are effectively invisible in the absence of a virus-hunting diagnostic—are simply not in the same league. Katherine J. Wu, The Atlantic, 13 July 2021 Turner stands by his company’s test and attributes Curative’s rapid growth to its ability to develop a simple diagnostic, build a robust supply chain and process millions of tests as other labs were overwhelmed. Los Angeles Times, 24 Mar. 2021 Accurate Knowledge Of The Team’s Issues Team-building activities should only be undertaken after a thorough diagnostic that surfaces the issues the team is facing. Expert Panel®, Forbes, 9 Mar. 2021 Doctors use a clinical diagnostic like a strep test to tell whether a patient is sick with a disease that can be treated with particular medicines. Caroline Chen, ProPublica, 1 Sep. 2020 See More

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

First Known Use of diagnostic


1625, in the meaning defined at sense 1a


1625, in the meaning defined at sense 1

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The first known use of diagnostic was in 1625

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Dictionary Entries Near diagnostic

diagnosis related group



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Last Updated

7 Aug 2022

Cite this Entry

“Diagnostic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diagnostic. Accessed 9 Aug. 2022.

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More Definitions for diagnostic


di·​ag·​nos·​tic | \ -ˈnäs-tik How to pronounce diagnostic (audio) \
variants: also diagnostical \ -​ti-​kəl How to pronounce diagnostic (audio) \

Medical Definition of diagnostic

 (Entry 1 of 2)

1 : of, relating to, or used in diagnosis
2 : using the methods of or yielding a diagnosis a diagnostic service diagnostic properties

Other Words from diagnostic

diagnostically \ -​ti-​k(ə-​)lē How to pronounce diagnostic (audio) \ adverb



Medical Definition of diagnostic (Entry 2 of 2)

: the art or practice of diagnosis often used in plural

More from Merriam-Webster on diagnostic

Nglish: Translation of diagnostic for Spanish Speakers

Britannica English: Translation of diagnostic for Arabic Speakers


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