diagnostic

dy-ug-NOSS-tik /ˌdaɪ.əɡˈnɒs.tɪk/
adjectivenounB2GRETOEFLIELTS
MedicalProfessional

Relating to the identification of a disease or condition through examination of symptoms and tests.

While 'screening' is for everyone, 'diagnostic' tests are specific to someone suspected of having a problem.

The story behind the word. From the Greek 'diagignōskein', meaning 'to distinguish' or 'to discern'. It combines 'dia' (through) and 'gignōskein' (to know).

Word relationships

  • analytical: Analytical is broader, referring to any logical breakdown, while diagnostic is specific to identifying a cause.
  • indicative: Indicative suggests a sign, whereas diagnostic implies a formal process of identification.
  • prognostic: Diagnostic looks at the current cause; prognostic looks at the future outcome.

Commonly confused with

  • prognostic: Diagnostic identifies what is wrong now; prognostic predicts how it will end.

Word family

  • diagnose (verb): To identify a disease.
  • diagnosis (noun): The identification of the nature of an illness.

Collocations

  • diagnostic tool
  • diagnostic criteria
  • diagnostic test
  • diagnostic imaging

Example sentences

  • "The physician ordered a diagnostic laparoscopy to investigate the cause of the patient's chronic abdominal pain." Medical procedure
  • "Diagnostic accuracy is the ability of a test to discriminate between the target condition and health." Clinical literature

Memory hook

Think of a 'Diagram' that helps you 'Know' (gnos) what is wrong. Know through the symptoms.

When not to use

Do not use for general problem-solving in casual contexts (e.g., 'a diagnostic for my broken toaster') unless you want to sound overly technical.

Fun facts

  • The term was first used in English in the late 17th century.

Related words

prognosis, pathology

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