cdr vs ci, What's the Difference?

Which to use

“cdr” is a noun and “ci” is an adverb - they look or sound alike but fill different roles in a sentence.

#39,697
“cdr” frequency rank: #264
“ci” frequency rank: 39961
confusion score

Side-by-Side Comparison

Feature	cdr	ci
Definition	La seconde partie du doublet en LISP, qui pointe le reste d’une liste.	ou (Utilisé uniquement dans les compositions, pas utilisé isolément) Ici.

Where the eye mixes cdr and ci

Muted = shared; highlighted = the visual trap. They share 1 letter in sequence.

3 ch

cdr

2 ch

Why the eye confuses cdr with ci

These two trip readers on the page rather than in the ear: cdr is \ku.dœʁ\ while ci is \si\. 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 adverb), which is usually the fastest check. Our composite confusion score for this pair is 39961, derived from the frequency rank of both members and their visual similarity.

cdr is recorded at frequency rank #39,697, classified as anoun, pronounced \ku.dœʁ\. ci is at rank #264, tagged as anadv, pronounced \si\.

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 39961, this pair ranks #244,063 of 440,172 scored French confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of cdr vs ci

Shared letters: c. Private to "cdr": dr. Private to "ci": i.

"cdr" · 3 letters · shape CCC · "ci" · 2 letters · shape CV

Frequently Asked Questions

Can "cdr" and "ci" be used interchangeably?

No - they are not even the same part of speech. "cdr" is a noun and "ci" an adverb, so a sentence built for one is usually ungrammatical with the other.

In ordinary French text, does "cdr" or "ci" show up more?

"ci" is the more common of the two: it sits at frequency rank #264 in our French list, against #39,697 for "cdr". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

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 "cdr" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "ci" - compare definitions side by side with the headword page. Word entry
This pair ranks #244,063 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
"cdr" and "ci" also get mixed up with nearby pairs, the highest-scored neighbour is "cdr vs ciro". Nearby pair

Confusion rank #244,063 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.