caisvscosWhat's the difference?

Quick tell: cais is a noun, cos is a pronoun, so they fill different roles in a sentence.

Which to use

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

#10,845
“cais” frequency rank
#27,810
“cos” frequency rank
38655
confusion score

Side-by-Side Comparison

Feature cais cos
Definition lugar à beira-mar, na margem do rio, nas estações de caminho-de-ferro ou do metropolitano apropriado para o embarque e desembarque de pessoas ou mercadorias qualquer coisa

Letter map: cais vs cos

Shared letters muted; letters that set cais and cos apart highlighted. Shared run: 2.

4 ch
cais
3 ch
cos

Part-of-speech tell for cais / cos

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: cais is anoun and cosapronoun. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 38655, derived from the frequency rank of both members and their visual similarity.

cais is recorded at frequency rank #10,845, classified as anoun, pronounced /ˈkajʃ/. cos is at rank #27,810, tagged as apron.

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 38655, this pair ranks #27,739 of 75,631 scored Portuguese confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of cais vs cos

Shared letters: cs. Private to "cais": ai. Private to "cos": o.

"cais" · 4 letters · shape CVVC  ·  "cos" · 3 letters · shape CVC

Known mistypes of this pair

  • caisacis · caiss · casi · ccais · cias

Frequently Asked Questions

Can "cais" and "cos" be used interchangeably?
No - they are not even the same part of speech. "cais" is a noun and "cos" a pronoun, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "cais" or "cos"?
"cais" is the more common of the two: it sits at frequency rank #10,845 in our Portuguese list, against #27,810 for "cos". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

Done with this confusable. These links stay specific to "cais" and "cos".

  • Full dictionary entry for "cais" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "cos" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #27,739 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
  • "cais" and "cos" also get mixed up with nearby pairs, the highest-scored neighbour is "coin vs cos". 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 #27,739 of 75,631 scored Portuguese pairs, corpus vintage 2026-09-03, not spelling advice.

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

Source: FrequencyWords open word-frequency list