ci vs cu, What's the Difference?

Which to use

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

#19,655
“ci” frequency rank: #4,716
“cu” frequency rank: 24371
confusion score

Side-by-Side Comparison

Feature	ci	cu
Definition	tu, pronome pessoal sujeito da segunda pessoa do singular:	extremidade do intestino grosso; ânus

Where the eye mixes ci and cu

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

2 ch

Visual trap between ci and cu

These two trip readers on the page rather than in the ear: ci is /tsi/ while cu is /ˈku/. Spoken aloud the problem disappears. In writing it persists, because they differ by a single letter - i in “ci” becomes u in “cu”, and the parts of speech differ too (pronoun vs noun), which is usually the fastest check. Our composite confusion score for this pair is 24371, derived from the frequency rank of both members and their visual similarity.

ci is recorded at frequency rank #19,655, classified as apron, pronounced /tsi/. cu is at rank #4,716, tagged as anoun, pronounced /ˈku/.

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 24371, this pair ranks #45,259 of 75,631 scored Portuguese confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of ci vs cu

Shared letters: c. Private to "ci": i. Private to "cu": u.

"ci" · 2 letters · shape CV · "cu" · 2 letters · shape CV

Frequently Asked Questions

Is swapping "ci" for "cu" ever safe?

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

Which is more common, "ci" or "cu"?

"cu" is the more common of the two: it sits at frequency rank #4,716 in our Portuguese list, against #19,655 for "ci". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

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

Full dictionary entry for "ci" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "cu" - compare definitions side by side with the headword page. Word entry
This pair ranks #45,259 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
"ci" and "cu" also get mixed up with nearby pairs, the highest-scored neighbour is "ci vs ciao". Nearby pair

Confusion rank #45,259 of 75,631 scored Portuguese pairs, corpus vintage 2026-09-03, not spelling advice.