diagnostic

American  

[dahy-uhg-nos-tik] / ˌdaɪ əgˈnɒs tɪk /

adjective

1. of, relating to, or used in diagnosis.

2. serving to identify or characterize; being a precise indication.

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noun

• diagnostics
  plural

1. diagnosis.

2. a symptom or characteristic of value in diagnosis.

3. Medicine/Medical. a device or substance used for the analysis or detection of diseases or other medical conditions.

4. Computers.

   1. a message output by a computer diagnosing an error in a computer program, computer system, or component device.

   2. a program or subroutine that produces such messages.

diagnostic British  

/ ˌdaɪəɡˈnɒstɪk /

adjective

1. of, relating to, or of value in diagnosis

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noun

1. med any symptom that provides evidence for making a specific diagnosis

2. a diagnosis

Other Word Forms

Derived Forms

• postdiagnostic
  adjective
• prediagnostic
  adjective
• diagnostically
  adverb

Inflected Forms

Nouns

• diagnostics
  plural

Etymology

Origin of diagnostic

1615–25; < Greek diagnōstikós, equivalent to diagnōst ( ós ) distinguished (akin to diágnōsis; see diagnosis) + -ikos -ic

Explanation

Anything diagnostic has to do with disease, especially figuring out which one a patient has. If your doctor wants to run diagnostic tests, then she isn't exactly sure what's wrong with you — so the tests will help diagnose you (figure out what's wrong). The TV show House is all about diagnostic tests: it features illnesses that are unusual and hard to determine. But anything diagnostic is trying to figure out what's wrong. A writing test could be called diagnostic if it's trying to determine how good or bad your writing skills are.

Example Sentences

See Examples For:

diagnostic diagnostics

It says subtypes have "no clinical value, diagnostic relevance or practical application".

From BBC ● Aug. 21, 2026

The NHS says it can be difficult to recognise autism in women, but Dame Uta says: "I am sceptical of late diagnosis. That's where I think the diagnostic process has become very superficial."

From BBC ● Aug. 21, 2026

They must maintain nurses, physicians, technicians, operating rooms, diagnostic equipment and emergency readiness around the clock.

From The Wall Street Journal ● Aug. 20, 2026

Researchers at LLE helped develop and maintain the improved diagnostic equipment that made those measurements possible.

From Science Daily ● Aug. 20, 2026

On the night of April 7, Mark Mills boarded a helicopter with a diagnostic crew to inspect preparations for one of the first tests when they ran into a sudden squall.

From "Big Science" by Michael Hiltzik

In April 2027, UChicago Medicine will open the AbbVie Foundation Cancer Pavilion, Chicago's first freestanding cancer pavilion, to bring advanced diagnostics, innovative treatments, translational discoveries, and comprehensive support to patients and the community.

From Science Daily ● Aug. 19, 2026

Revenue gains in advanced imaging and pharmaceutical diagnostics offset a 13% decline in GE HealthCare’s patient care solutions segment.

From The Wall Street Journal ● Jul. 29, 2026

“AI-driven drug discovery, clinical development and diagnostics are beginning to improve productivity across the sector, while life science tools appear to be emerging from a multiyear destocking cycle.”

From MarketWatch ● Jul. 15, 2026

The advance could help pave the way for phonon lasers, a technology with potential uses in communications, medical diagnostics, and advanced sensing.

From Science Daily ● Jul. 2, 2026

I spent the day running full diagnostics on every system in the Hab.

From "The Martian" by Andy Weir