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

A full diagnostic panel informs every guest’s customized itinerary.

From The Wall Street Journal ● Oct. 2, 2026

The team now hopes that the biological pathways identified in the study could eventually contribute to broader diagnostic tools and potentially treatments that could be relevant to more than one chronic condition.

From Science Daily ● Oct. 2, 2026

Study co-author Dr. Aysha Al-Ani cautioned that the findings are unlikely to produce a new diagnostic test or therapy immediately.

From Science Daily ● Sep. 20, 2026

Last year, we reported that nearly £6m had been paid by the trust over six years to breast cancer diagnostic clinics and surgery companies run privately by Bhatti.

From BBC ● Sep. 17, 2026

The study concluded that the effect on Americans of radioactive emissions from nuclear tests was vastly outweighed by their exposure to diagnostic X-rays and other common sources.

From "Big Science" by Michael Hiltzik

A.I.-powered diagnostics distill all of this into one clear picture of your entire body, in 360-degree, piercing-into-the-soul, high-resolution detail.

From Slate ● Oct. 8, 2026

"I have to make it clear - we don't have diagnostics to test for Ebola. It's just about temperature," he said.

From BBC ● Oct. 7, 2026

"Preparedness planning should extend beyond diagnostics, vaccines, and therapeutics to include operational readiness for multinational outbreak response," she said.

From Science Daily ● Sep. 20, 2026

Join leading investors, policymakers, healthcare executives and innovators for high-level networking and newsroom-led conversations on the trends reshaping healthcare—from GLP-1s and AI diagnostics to mental health, longevity and the cost of care.

From The Wall Street Journal ● Sep. 10, 2026

Physician recommended diagnostics and referred to specialist for ruling out infection or cancer.

From "The Immortal Life of Henrietta Lacks" by Rebecca Skloot