ob vs os, What's the Difference?

Which to use

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

#28,692
“ob” frequency rank: #19
“os” frequency rank: 28711
confusion score

Side-by-Side Comparison

Feature	ob	os
Definition	eu, pronome pessoal do caso nominativo da primeira pessoa do singular;	usado para apontar um nome definido, único

Where the eye mixes ob and os

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

2 ch

Look-alike desk: ob vs os

These two trip readers on the page rather than in the ear: ob is /ob/ while os is /uʃ/, /us/ (menos frequente); enfático: /oʃ/, /os/ (menos frequente). Spoken aloud the problem disappears. In writing it persists, because they differ by a single letter - b in “ob” becomes s in “os”, and the parts of speech differ too (pronoun vs article), which is usually the fastest check. Our composite confusion score for this pair is 28711, derived from the frequency rank of both members and their visual similarity.

ob is recorded at frequency rank #28,692, classified as apron, pronounced /ob/. 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 28711, this pair ranks #40,084 of 75,631 scored Portuguese confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of ob vs os

Shared letters: o. Private to "ob": b. Private to "os": s.

"ob" · 2 letters · shape VC · "os" · 2 letters · shape VC

Frequently Asked Questions

Do "ob" and "os" mean the same thing in a sentence?

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

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

"os" is the more common of the two: it sits at frequency rank #19 in our Portuguese list, against #28,692 for "ob". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

After this comparison

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

Full dictionary entry for "ob" 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 #40,084 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
"ob" and "os" also get mixed up with nearby pairs, the highest-scored neighbour is "ob vs oni". Nearby pair

Confusion rank #40,084 of 75,631 scored Portuguese pairs, corpus vintage 2026-09-03, not spelling advice.