# diagnostic

> English word · Adjective · IPA /daɪ.əɡˈnɒs.tɪk/ · frequency rank #9,165

## Definitions
1. Of, or relating to diagnosis.
2. Characteristic of a particular disease.
3. Serving to indicate or specify a particular item or thing within a group of similar things.
4. Intended to assess a student's preexisting knowledge on the material being taught.
5. (of a skeletal or genetic feature) Characteristic of a particular taxon or clade.

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

## Easily confused with
- **diagnostics** (https://plainspell.com/en/vs/diagnostic-vs-diagnostics)
- **diagnosis** (https://plainspell.com/en/vs/diagnosis-vs-diagnostic)

## Common misspellings (15)
`daignostic`, `ddiagnostic`, `diaggnostic`, `diagnnostic`, `diagnositc`, `diagnosstic`, `diagnostci`, `diagnosticc`, `diagnosttic`, `diagnotsic`, `diagnsotic`, `diagonstic`, `diangostic`, `diganostic`, `idagnostic`

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/diagnostic