# diagnostic

/ˌdaɪəɡˈnɑstɪk/ (US) · /dˌaɪəɡnˈɒstɪk/ (UK)

Source: https://englishreference.com/word/diagnostic
Updated: 2026-06-20

## Senses

### 1. medical/technical identification

adjective · CEFR B2 · Technical

used to help identify a disease or a technical problem.

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

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

adjective · CEFR B2 · Academic

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

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

- We took a diagnostic quiz on the first day of the Spanish class.
- The diagnostic assessment revealed that while the students had strong vocabulary skills, they struggled significantly with complex grammatical structures.

### 3. a tool or test

noun · CEFR C1 · Technical

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

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

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

## Examples

- The doctor ordered a diagnostic test to check his heart.
- Teachers use a diagnostic assessment at the start of the year to see which grammar points students already understand.
- The software includes a diagnostic suite that monitors system performance in real time to identify potential hardware failures before they cause a total crash.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.