Mistook vs. Mistaken
Use “mistook” for the simple past of the verb “mistake” and “mistaken” as its past participle, especially after have/has/had. The guide preserves documented regional or alternate forms rather than treating the pair as an absolute binary.
Use “mistook” for the simple past of the verb “mistake” and “mistaken” as its past participle, especially after have/has/had.
Key details
Choose the right form
| Sentence need | Use | Example |
|---|---|---|
| simple past | mistook | The sentence uses mistook as a simple-past form of “mistake.” |
| past participle after have/has/had | mistaken | The sentence uses mistaken after an auxiliary. |
Usage notes
This guide addresses the verb paradigm; “mistaken” can also be used adjectivally.
Further guidance
Core difference
“Mistook” is the simple-past form of the verb “mistake”; “mistaken” is the past participle and can also function adjectivally in other contexts.
Fast Test
For a standalone finite past-tense use of the verb, choose “mistook.” After have/has/had, choose “mistaken.”
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
- Mistake — Cambridge Dictionary (opens in a new tab)Cambridge University Press · Direct verb-form evidence for mistake, mistook, mistaken.