Which to use
“RSF” and “rus” are a confusable French pair: similar on the page, but distinct in meaning, check the gloss before you choose.
- #44,703
- “RSF” frequency rank
- #37,537
- “rus” frequency rank
- 82240
- confusion score
Side-by-Side Comparison
| Feature | RSF | rus |
|---|---|---|
| Definition | Abréviation de réacteur à sels fondus. | Pluriel de ru. |
Where the eye mixes RSF and rus
Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.
Why the eye confuses RSF with rus
A purely visual mix-up. RSF (\ɛ.ʁɛ.sɛf\) and rus (\ʁy\) are said differently, so reading them aloud is the quickest way to catch the wrong one. On the page they stay close: they share most of their letters but differ in 2 positions. Our composite confusion score for this pair is 82240, derived from the frequency rank of both members and their visual similarity.
RSF is recorded at frequency rank #44,703, classified as anoun, pronounced \ɛ.ʁɛ.sɛf\. rus is at rank #37,537, tagged as anoun, pronounced \ʁy\.
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 82240, this pair ranks #17,115 of 440,172 scored French confusable pairs - among the most confusable pairs.
Orthographic DNA of RSF vs rus
Shared letters: rs. Private to "RSF": f. Private to "rus": u.
"RSF" · 3 letters · shape CCC · "rus" · 3 letters · shape CVC
Frequently Asked Questions
Is swapping "RSF" for "rus" ever safe?
In ordinary French text, does "RSF" or "rus" show up more?
Useful next steps
Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.
- Full dictionary entry for "RSF" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "rus" - compare definitions side by side with the headword page. Word entry
- This pair ranks #17,115 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
- "RSF" and "rus" also get mixed up with nearby pairs, the highest-scored neighbour is "rog vs RSF". Nearby pair
Confusion rank #17,115 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.