Which to use
“insu” is a noun and “iu” is a pronoun - they look or sound alike but fill different roles in a sentence.
- #12,987
- “insu” frequency rank
- #46,833
- “iu” frequency rank
- 59820
- confusion score
Side-by-Side Comparison
| Feature | insu | iu |
|---|---|---|
| Definition | Utilisé uniquement dans la locution figée à l’insu de quelqu'un, et, dans les locutions analogues, à mon insu, à votre insu… C’est-à-dire la chose n'étant pas sue de quelqu'un, de moi, de vous, etc. | Je. |
Where the eye mixes insu and iu
Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.
Why the eye confuses insu with iu
These two trip readers on the page rather than in the ear: insu is \ɛ̃.sy\ while iu is \ˈiu\. Spoken aloud the problem disappears. In writing it persists, because they differ by 2 letter(s) in length, and the parts of speech differ too (noun vs pronoun), which is usually the fastest check. Our composite confusion score for this pair is 59820, derived from the frequency rank of both members and their visual similarity.
insu is recorded at frequency rank #12,987, classified as anoun, pronounced \ɛ̃.sy\. iu is at rank #46,833, tagged as apron, pronounced \ˈiu\.
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 59820, this pair ranks #101,015 of 440,172 scored French confusable pairs - among the most confusable pairs.
Orthographic DNA of insu vs iu
Shared letters: iu. Private to "insu": ns. Private to "iu": -.
"insu" · 4 letters · shape VCCV · "iu" · 2 letters · shape VV
Known mistypes of this pair
- insu ← innsu · inssu · inus · isnu · nisu
Frequently Asked Questions
Can "insu" and "iu" be used interchangeably?
Frequency check: "insu" vs "iu" - which ranks higher?
What to do next
Eye-level mix-up between "insu" and "iu" is sorted above. Next: full entries or other pairs that share a letter shape.
- Full dictionary entry for "insu" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "iu" - compare definitions side by side with the headword page. Word entry
- This pair ranks #101,015 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
- "insu" and "iu" also get mixed up with nearby pairs, the highest-scored neighbour is "isi vs iu". 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 #101,015 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.