Which to use
“fioul” is a noun and “foll” is an adjective - they look or sound alike but fill different roles in a sentence.
- #27,065
- “fioul” frequency rank
- #35,043
- “foll” frequency rank
- 62108
- confusion score
Side-by-Side Comparison
| Feature | fioul | foll |
|---|---|---|
| Definition | Distillat lourd du pétrole, utilisé comme combustible pour des installations de chauffage domestiques ou industrielles, comme carburant pour les gros moteurs diesels. | Fou. |
Where the eye mixes fioul and foll
Muted = shared; highlighted = the visual trap. They share 3 letters in sequence.
Visual trap between fioul and foll
These two trip readers on the page rather than in the ear: fioul is \fjul\ while foll is \ˈfɔlː\. 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 adjective), which is usually the fastest check. Our composite confusion score for this pair is 62108, derived from the frequency rank of both members and their visual similarity.
fioul is recorded at frequency rank #27,065, classified as anoun, pronounced \fjul\. foll is at rank #35,043, tagged as anadj, pronounced \ˈfɔlː\.
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 62108, this pair ranks #88,784 of 440,172 scored French confusable pairs - among the most confusable pairs.
Orthographic DNA of fioul vs foll
Shared letters: flo. Private to "fioul": iu. Private to "foll": -.
"fioul" · 5 letters · shape CVVVC · "foll" · 4 letters · shape CVCC
Known mistypes of this pair
Frequently Asked Questions
Can "fioul" and "foll" be used interchangeably?
In ordinary French text, does "fioul" or "foll" show up more?
After this comparison
Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.
- Full dictionary entry for "fioul" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "foll" - compare definitions side by side with the headword page. Word entry
- This pair ranks #88,784 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
- "fioul" and "foll" also get mixed up with nearby pairs, the highest-scored neighbour is "Feld vs foll". 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 #88,784 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.