Which to use
“ru” and “rust” are a confusable French pair: similar on the page, but distinct in meaning, check the gloss before you choose.
- #16,467
- “ru” frequency rank
- #37,050
- “rust” frequency rank
- 53517
- confusion score
Side-by-Side Comparison
| Feature | ru | rust |
|---|---|---|
| Definition | Petit ruisseau. | Rouille. |
Where the eye mixes ru and rust
Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.
Why the eye confuses ru with rust
A purely visual mix-up. ru (\ʁy\) and rust (\ɻʌst\) are said differently, so reading them aloud is the quickest way to catch the wrong one. On the page they stay close: they differ by 2 extra letter(s) - “ru” sits inside “rust”. Our composite confusion score for this pair is 53517, derived from the frequency rank of both members and their visual similarity.
ru is recorded at frequency rank #16,467, classified as anoun, pronounced \ʁy\. rust is at rank #37,050, tagged as anoun, pronounced \ɻʌst\.
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 53517, this pair ranks #140,174 of 440,172 scored French confusable pairs - roughly mid-pack for confusability.
Orthographic DNA of ru vs rust
Shared letters: ru. Private to "ru": -. Private to "rust": st.
"ru" · 2 letters · shape CV · "rust" · 4 letters · shape CVCC
Known mistypes of this pair
- rust ← rrust · rsut · russt · rustt · ruts · urst
Frequently Asked Questions
Can "ru" and "rust" be used interchangeably?
In ordinary French text, does "ru" or "rust" show up more?
What to do next
Eye-level mix-up between "ru" and "rust" is sorted above. Next: full entries or other pairs that share a letter shape.
- Full dictionary entry for "ru" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "rust" - compare definitions side by side with the headword page. Word entry
- This pair ranks #140,174 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
- "ru" and "rust" also get mixed up with nearby pairs, the highest-scored neighbour is "rouet vs rust". Nearby pair
- Recorded mistypes exist for at least one side of this pair, useful when a spell-checker or OCR lands on the wrong form. See mistypes
Confusion rank #140,174 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.