caosvscasoTell them apart

Quick tell: caos is a noun, caso is a conjunction, so they fill different roles in a sentence.

Which to use

“caos” is a noun and “caso” is a conjunction - they look or sound alike but fill different roles in a sentence.

#4,128
“caos” frequency rank
#181
“caso” frequency rank
4309
confusion score

Side-by-Side Comparison

Feature caos caso
Definition espaço limitado e amorfo que precedeu à criação do cosmo na hipótese de; se

Where the eye mixes caos and caso

Muted = shared; highlighted = the visual trap. They share 3 letters in sequence.

4 ch
caos
4 ch
caso

Why the eye confuses caos with caso

These two trip readers on the page rather than in the ear: caos is /ˈkaws/ while caso is /ˈka.zu/. Spoken aloud the problem disappears. In writing it persists, because they differ only by swapping two adjacent letters (os ↔ so) - a transposition the eye reads straight past, and the parts of speech differ too (noun vs conjunction), which is usually the fastest check. Our composite confusion score for this pair is 4309, derived from the frequency rank of both members and their visual similarity.

caos is recorded at frequency rank #4,128, classified as anoun, pronounced /ˈkaws/. caso is at rank #181, tagged as aconj, pronounced /ˈka.zu/.

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 4309, this pair ranks #70,638 of 75,631 scored Portuguese confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of caos vs caso

Shared letters: acos. Private to "caos": -. Private to "caso": -.

"caos" · 4 letters · shape CVVC  ·  "caso" · 4 letters · shape CVCV

Known mistypes of this pair

  • caosacos · caoss · ccaos · coas
  • casoacso · casso · ccaso · csao

Frequently Asked Questions

Can "caos" and "caso" be used interchangeably?
No - they are not even the same part of speech. "caos" is a noun and "caso" a conjunction, so a sentence built for one is usually ungrammatical with the other.
In ordinary Portuguese text, does "caos" or "caso" show up more?
"caso" is the more common of the two: it sits at frequency rank #181 in our Portuguese list, against #4,128 for "caos". 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 "caos" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "caso" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #70,638 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
  • "caos" and "caso" also get mixed up with nearby pairs, the highest-scored neighbour is "caos vs ciao". 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 #70,638 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