di·ag·nos·tic
ˌdī-ig-ˈnä-stik 
-əg-
variants
or less commonly diagnostical
ˌdī-ig-ˈnä-sti-kəl
-əg-
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
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
Harriet Marsden, TheWeek, 20 Feb. 2026
That unpredictability is one reason why clinicians and patients need to be aware of a PE and consider it as part of the diagnostic possibilities.
—Katia Hetter, CNN Money, 18 Feb. 2026
Brian Steinberg, Variety, 23 Feb. 2026
Using diagnostics, wearables and specialized coaching, the program is designed around the different stages of a woman’s life and health journey, and already has its own waitlist.
—Robert Frank, CNBC, 20 Feb. 2026
See All Example Sentences for diagnostic
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Adjective
There is currently no one diagnostic test; just different tests, that typically take hours, to confirm the presence, and possibly the type, of infection.
—Harriet Marsden, TheWeek, 20 Feb. 2026
That unpredictability is one reason why clinicians and patients need to be aware of a PE and consider it as part of the diagnostic possibilities.
—Katia Hetter, CNN Money, 18 Feb. 2026
Noun
Attia placed an emphasis on exercise, protein consumption and early diagnostics.
—Brian Steinberg, Variety, 23 Feb. 2026
Using diagnostics, wearables and specialized coaching, the program is designed around the different stages of a woman’s life and health journey, and already has its own waitlist.
—Robert Frank, CNBC, 20 Feb. 2026
See All Example Sentences for diagnostic
Cite this Entry
“Diagnostic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diagnostic. Accessed 25 Feb. 2026.
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