ono vs os, What's the Difference?

Which to use

“ono” is a pronoun and “os” is an article - they look or sound alike but fill different roles in a sentence.

#37,444
“ono” frequency rank: #19
“os” frequency rank: 37463
confusion score

Side-by-Side Comparison

Feature	ono	os
Definition	pronome pessoal neutro do caso nominativo da terceira pessoa do singular	usado para apontar um nome definido, único

Letter map: ono vs os

Shared letters muted; letters that set ono and os apart highlighted. Shared run: 1.

3 ch

ono

2 ch

Part-of-speech tell for ono / os

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: ono is apronoun and osanarticle. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 37463, derived from the frequency rank of both members and their visual similarity.

ono is recorded at frequency rank #37,444, classified as apron. os is at rank #19, tagged as anarticle, pronounced /uʃ/, /us/ (menos frequente); enfático: /oʃ/, /os/ (menos frequente).

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 37463, this pair ranks #29,147 of 75,631 scored Portuguese confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of ono vs os

Shared letters: o. Private to "ono": n. Private to "os": s.

"ono" · 3 letters · shape VCV · "os" · 2 letters · shape VC

Frequently Asked Questions

Is swapping "ono" for "os" ever safe?

No - they are not even the same part of speech. "ono" is a pronoun and "os" an article, so a sentence built for one is usually ungrammatical with the other.

In ordinary Portuguese text, does "ono" or "os" show up more?

"os" is the more common of the two: it sits at frequency rank #19 in our Portuguese list, against #37,444 for "ono". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

What to do next

Pair "ono" vs "os" is on the table, pick a follow-up below.

Full dictionary entry for "ono" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "os" - compare definitions side by side with the headword page. Word entry
This pair ranks #29,147 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
"ono" and "os" also get mixed up with nearby pairs, the highest-scored neighbour is "oni vs ono". Nearby pair

Confusion rank #29,147 of 75,631 scored Portuguese pairs, corpus vintage 2026-09-03, not spelling advice.