Which to use
“rust” is a noun and “rusty” is an adjective - they look or sound alike but fill different roles in a sentence.
- #10,604
- “rust” frequency rank
- #12,855
- “rusty” frequency rank
- 23459
- confusion score
Side-by-Side Comparison
| Feature | rust | rusty |
|---|---|---|
| Definition | The deteriorated state of iron or steel as a result of moisture and oxidation; it consists mostly of iron(III) oxide (ferric oxide) and iron(II) oxide (ferrous oxide). | Marked or corroded by rust. |
Where the spellings diverge
Shared letters are muted; the letters that actually set rust and rusty apart are highlighted. They share 4 letters in sequence, which is exactly why the eye skips the difference.
Spelling & Dictionary Insight
rust and rusty form a confusable pair in the English index, two distinct headwords that are easily confused because they look alike, sound alike, or both. They differ by 1 extra letter(s) - “rust” sits inside “rusty” - close enough that the eye skips over the difference, far enough that meaning fully diverges. Our composite confusion score for this pair is 23459, derived from the frequency rank of both members and their visual similarity.
rust is recorded at frequency rank #10,604, classified as anoun, pronounced /ɹʌst/. rusty is at rank #12,855, tagged as anadj, pronounced /ˈɹʌsti/.
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 23459, this pair ranks #409,105 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.
Frequency comparison
Frequently Asked Questions
Can "rust" and "rusty" be used interchangeably?
Remembering rust vs rusty
The fastest way to pick the right one every time.
- Check the role first: if you need a noun, it's “rust”; for an adjective, it's “rusty”.
- See each word in full, definition, IPA, etymology and its other confusables. Full “rust” entry
- Browse more pairs most likely to be confused. Most confusable