Which to use
“sai” is a noun and “si” is a conjunction - they look or sound alike but fill different roles in a sentence.
- #26,527
- “sai” frequency rank
- #46
- “si” frequency rank
- 26573
- confusion score
Side-by-Side Comparison
| Feature | sai | si |
|---|---|---|
| Definition | Saï (arme japonaise). | Dans le cas où, à condition que, supposé que. Note d’usage : Conjonction qui introduit une condition (suivie d’une conséquence) ou une supposition qui peut être supprimée en utilisant un conditionnel. |
Where the eye mixes sai and si
Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.
Look-alike desk: sai vs si
These two trip readers on the page rather than in the ear: sai is \ˈsaɪ\ while si is \si\. Spoken aloud the problem disappears. In writing it persists, because they differ by 1 letter(s) in length, and the parts of speech differ too (noun vs conjunction), which is usually the fastest check. Our composite confusion score for this pair is 26573, derived from the frequency rank of both members and their visual similarity.
sai is recorded at frequency rank #26,527, classified as anoun, pronounced \ˈsaɪ\. si is at rank #46, tagged as aconj, pronounced \si\.
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 26573, this pair ranks #334,163 of 440,172 scored French confusable pairs - a relatively easy-to-tell-apart pair.
Orthographic DNA of sai vs si
Shared letters: is. Private to "sai": a. Private to "si": -.
"sai" · 3 letters · shape CVV · "si" · 2 letters · shape CV
Frequently Asked Questions
Is swapping "sai" for "si" ever safe?
In ordinary French text, does "sai" or "si" show up more?
Useful next steps
Eye-level mix-up between "sai" and "si" is sorted above. Next: full entries or other pairs that share a letter shape.
- Full dictionary entry for "sai" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "si" - compare definitions side by side with the headword page. Word entry
- This pair ranks #334,163 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
- "sai" and "si" also get mixed up with nearby pairs, the highest-scored neighbour is "sai vs suu". Nearby pair
Confusion rank #334,163 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.