CFFvsclefConfusable pair

Which to use

“CFF” and “clef” are a confusable French pair: similar on the page, but distinct in meaning, check the gloss before you choose.

#46,639
“CFF” frequency rank
#6,063
“clef” frequency rank
52702
confusion score

Side-by-Side Comparison

Feature CFF clef
Definition Société anonyme (détenue à 100 % par la Confédération suisse) exploitant les chemins de fer suisses. Variante orthographique de clé.

Where the eye mixes CFF and clef

Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.

3 ch
CFF
4 ch
clef

Why the eye confuses CFF with clef

A purely visual mix-up. CFF (\se.ɛf.ɛf\) and clef (\kle\) 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 52702, derived from the frequency rank of both members and their visual similarity.

CFF is recorded at frequency rank #46,639, classified as anoun, pronounced \se.ɛf.ɛf\. clef is at rank #6,063, tagged as anoun, pronounced \kle\.

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 52702, this pair ranks #145,868 of 440,172 scored French confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of CFF vs clef

Shared letters: cf. Private to "CFF": -. Private to "clef": el.

"CFF" · 3 letters · shape CCC  ·  "clef" · 4 letters · shape CCVC

Known mistypes of this pair

  • clefcclef · celf · cleff · clfe · cllef · lcef

Frequently Asked Questions

Do "CFF" and "clef" mean the same thing in a sentence?
No. They are said differently (\se.ɛf.ɛf\ versus \kle\) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
In ordinary French text, does "CFF" or "clef" show up more?
"clef" is the more common of the two: it sits at frequency rank #6,063 in our French list, against #46,639 for "CFF". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Useful next steps

Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.

  • Full dictionary entry for "CFF" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "clef" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #145,868 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
  • "CFF" and "clef" also get mixed up with nearby pairs, the highest-scored neighbour is "CCE vs CFF". 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 #145,868 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list