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
NPR, 21 Oct. 2025
The organization has a patient care center, with educational information, guidance on screening and diagnostic work, and ways to get emotional and financial support.
—Korin Miller, Flow Space, 20 Oct. 2025
Ryley Amond, CNBC, 12 Oct. 2025
The McMaster team’s broader research highlights how integrating biosensors, wearables, and AI could revolutionize diagnostics for women’s health — from reproductive conditions to cancer and osteoporosis.
—Neetika Walter, Interesting Engineering, 11 Oct. 2025
See All Example Sentences for diagnostic
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
Hill and his colleagues acknowledge that their study has limitations, such as relying on diagnostic codes - which aren't necessarily equivalent to actual allergy rates.
—NPR, 21 Oct. 2025
The organization has a patient care center, with educational information, guidance on screening and diagnostic work, and ways to get emotional and financial support.
—Korin Miller, Flow Space, 20 Oct. 2025
Noun
This insurance provides coverage for illnesses, diagnostics, accidents, supportive care and more.
—Ryley Amond, CNBC, 12 Oct. 2025
The McMaster team’s broader research highlights how integrating biosensors, wearables, and AI could revolutionize diagnostics for women’s health — from reproductive conditions to cancer and osteoporosis.
—Neetika Walter, Interesting Engineering, 11 Oct. 2025
See All Example Sentences for diagnostic
Cite this Entry
“Diagnostic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diagnostic. Accessed 23 Oct. 2025.
Copy CitationMedical Definition
Love words? Need even more definitions?
Merriam-Webster unabridged
Share