Which to use
“impair” is a verb and “impaired” is an adjective - they look or sound alike but fill different roles in a sentence.
- #31,616
- “impair” frequency rank
- #11,558
- “impaired” frequency rank
- 43174
- confusion score
Side-by-Side Comparison
| Feature | impair | impaired |
|---|---|---|
| Definition | To weaken; to affect negatively; to have a diminishing effect on. | Rendered less effective. |
Where the spellings diverge
Shared letters are muted; the letters that actually set impair and impaired apart are highlighted. They share 6 letters in sequence, which is exactly why the eye skips the difference.
Spelling & Dictionary Insight
These two trip readers on the page rather than in the ear: impair is /ɪmˈpɛə(ɹ)/ while impaired is /ɪmˈpɛrd/. Spoken aloud the problem disappears. In writing it persists, because they differ by 2 extra letter(s) - “impair” sits inside “impaired”, and the parts of speech differ too (verb vs adjective), which is usually the fastest check. Our composite confusion score for this pair is 43174, derived from the frequency rank of both members and their visual similarity.
impair is recorded at frequency rank #31,616, classified as averb, pronounced /ɪmˈpɛə(ɹ)/. impaired is at rank #11,558, tagged as anadj, pronounced /ɪmˈpɛrd/.
Glosses for this pair are partially populated in our dataset, but the full side-by-side definitions above should still guide you to the right choice.
With a confusion score of 43174, this pair ranks #242,525 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.
Orthographic DNA of impair vs impaired
Shared letters: aimpr. Private to "impair": -. Private to "impaired": de.
"impair" · 6 letters · shape VCCVVC · "impaired" · 8 letters · shape VCCVVCVC
Known mistypes of this pair
Frequency comparison
Frequently Asked Questions
Can "impair" and "impaired" be used interchangeably?
Which is more common, "impair" or "impaired"?
Remembering impair vs impaired
The fastest way to pick the right one every time.
- Check the role first: if you need a verb, it's “impair”; for an adjective, it's “impaired”.
- See each word in full, definition, IPA, etymology and its other confusables. Full “impair” entry
- Browse more pairs most likely to be confused. Most confusable