Which to use
“filament” and “firmament” are a confusable French pair: similar on the page, but distinct in meaning, check the gloss before you choose.
- #40,271
- “filament” frequency rank
- #42,340
- “firmament” frequency rank
- 82611
- confusion score
Side-by-Side Comparison
| Feature | filament | firmament |
|---|---|---|
| Definition | Petit fil, petit brin long et délié, semblable à celui qui se tire de l’écorce du chanvre ou du lin. | Sphère au-dessus des planètes qui environne la terre et à laquelle les étoiles fixes sont considérées attachées. |
Where the eye mixes filament and firmament
Muted = shared; highlighted = the visual trap. They share 7 letters in sequence. filament runs 8 letters (CVCVCVCC) against firmament's 9 (CVCCVCVCC) - the length gap alone is often enough to separate them once you know to check it.
Visual trap between filament and firmament
A purely visual mix-up. filament (\fi.la.mɑ̃\) and firmament (\fiʁ.ma.mɑ̃\) are said differently, so reading them aloud is the quickest way to catch the wrong one. On the page they stay close: they differ by 1 letter(s) in length. Our composite confusion score for this pair is 82611, derived from the frequency rank of both members and their visual similarity.
filament is recorded at frequency rank #40,271, classified as anoun, pronounced \fi.la.mɑ̃\. firmament is at rank #42,340, tagged as anoun, pronounced \fiʁ.ma.mɑ̃\.
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 82611, this pair ranks #16,376 of 440,172 scored French confusable pairs - among the most confusable pairs.
Orthographic DNA of filament vs firmament
Shared letters: aefimnt. Private to "filament": l. Private to "firmament": r.
"filament" · 8 letters · shape CVCVCVCC · "firmament" · 9 letters · shape CVCCVCVCC
Known mistypes of this pair
Frequently Asked Questions
Is swapping "filament" for "firmament" ever safe?
In ordinary French text, does "filament" or "firmament" show up more?
After this comparison
Visual near-miss handled. Browse the word pages or a neighbour when the next look-alike shows up.
- Full dictionary entry for "filament" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "firmament" - compare definitions side by side with the headword page. Word entry
- This pair ranks #16,376 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
- "filament" and "firmament" also get mixed up with nearby pairs, the highest-scored neighbour is "filament vs filmant". 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 #16,376 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.