cemvscosWhat's the difference?

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

Which to use

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

#3,188
“cem” frequency rank
#27,810
“cos” frequency rank
30998
confusion score

Side-by-Side Comparison

Feature cem cos
Definition número equivalente a dez dezenas; cardinalidade de um conjunto que contenha uma centena de elementos distintos; representado pelo símbolo 100 (algarismos arábicos) ou C (algarismos romanos) qualquer coisa

Letter map: cem vs cos

Shared letters muted; letters that set cem and cos apart highlighted. Shared run: 1.

3 ch
cem
3 ch
cos

Role in the sentence - cem and cos

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: cem is anum and cosapronoun. On the page they share most of their letters but differ in 2 positions. Our composite confusion score for this pair is 30998, derived from the frequency rank of both members and their visual similarity.

cem is recorded at frequency rank #3,188, classified as anum, pronounced /ˈsɐ̃j̃/. 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 30998, this pair ranks #37,229 of 75,631 scored Portuguese confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of cem vs cos

Shared letters: c. Private to "cem": em. Private to "cos": os.

"cem" · 3 letters · shape CVC  ·  "cos" · 3 letters · shape CVC

Frequently Asked Questions

Can "cem" and "cos" be used interchangeably?
No - they are not even the same part of speech. "cem" is a num and "cos" a pronoun, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "cem" or "cos"?
"cem" is the more common of the two: it sits at frequency rank #3,188 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.

Useful next steps

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

  • Full dictionary entry for "cem" 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 #37,229 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
  • "cem" and "cos" also get mixed up with nearby pairs, the highest-scored neighbour is "coin vs cos". Nearby pair

Confusion rank #37,229 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