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diagnostic

adj. · n.
US //ˌdaɪəɡˈnɑstɪk// UK //dˌaɪəɡnˈɒstɪk// di·ag·nos·tic
  1. 1 medical/technical identification (adj.)
    B2 Upper Intermediate Technical Medicine

    used to help identify a disease or a technical problem.

    relating to or used in the identification of a medical condition or a technical malfunction.

    Example

    The doctor ordered a diagnostic test to see why the patient was feeling dizzy.

    Example

    The hospital invested in advanced diagnostic imaging equipment to improve the accuracy of early-stage cancer detection.

    Usage

    Often modifies nouns like 'test', 'tool', or 'procedure'.
  2. 2 educational assessment (adj.)
    B2 Upper Intermediate Academic Education

    a test given at the start of a course to see what you already know.

    designed to assess a learner's strengths, weaknesses, and prior knowledge before instruction begins.

    Example

    We took a diagnostic quiz on the first day of the Spanish class.

    Example

    The diagnostic assessment revealed that while the students had strong vocabulary skills, they struggled significantly with complex grammatical structures.
    • pre assessment
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  1. 3 a tool or test (n.)
    C1 Advanced Technical Computing

    a specific test or program used to find a fault or problem.

    a procedure, program, or tool used to identify the cause of a problem or the nature of a condition.

    Example

    The mechanic ran a diagnostic on the car's engine to find the leak.

    Example

    After the system crash, the IT department ran a full suite of diagnostics to determine if the failure was hardware-related or a software bug.

    Usage

    Frequently used in the plural form 'diagnostics' when referring to computer routines.
Origin

From Ancient Greek διαγνωστικός (diagnōstikós), adjective from διαγιγνώσκω (diagignṓskō, “to distinguish, diagnose”).

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