Which to use
“iec” is a verb and “ISF” is a name - they look or sound alike but fill different roles in a sentence.
- #48,589
- “iec” frequency rank
- #17,462
- “ISF” frequency rank
- 66051
- confusion score
Side-by-Side Comparison
| Feature | iec | ISF |
|---|---|---|
| Definition | Deuxième personne du pluriel du présent du verbe ié. | Impôt déclaratif payé par les personnes physiques, célibataires ou en couple, possédant un patrimoine imposable dont la valeur nette est supérieure à un seuil fixé par la loi. |
Where the eye mixes iec and ISF
Muted = shared; highlighted = the visual trap. They share 1 letter in sequence.
Why the eye confuses iec with ISF
These two trip readers on the page rather than in the ear: iec is \iˈɛʃ\ while ISF is \i ɛ.s‿ɛf\. Spoken aloud the problem disappears. In writing it persists, because they share most of their letters but differ in 2 positions, and the parts of speech differ too (verb vs name), which is usually the fastest check. Our composite confusion score for this pair is 66051, derived from the frequency rank of both members and their visual similarity.
iec is recorded at frequency rank #48,589, classified as averb, pronounced \iˈɛʃ\. ISF is at rank #17,462, tagged as aname, pronounced \i ɛ.s‿ɛf\.
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 66051, this pair ranks #69,552 of 440,172 scored French confusable pairs - among the most confusable pairs.
Orthographic DNA of iec vs ISF
Shared letters: i. Private to "iec": ce. Private to "ISF": fs.
"iec" · 3 letters · shape VVC · "ISF" · 3 letters · shape VCC
Frequently Asked Questions
Do "iec" and "ISF" mean the same thing in a sentence?
Frequency check: "iec" vs "ISF" - which ranks higher?
Useful next steps
Visual near-miss handled. Browse the word pages or a neighbour when the next look-alike shows up.
- Full dictionary entry for "iec" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "ISF" - compare definitions side by side with the headword page. Word entry
- This pair ranks #69,552 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
- "iec" and "ISF" also get mixed up with nearby pairs, the highest-scored neighbour is "iec vs isi". Nearby pair
Confusion rank #69,552 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.