Ob vs os, What's the Difference?

Which to use

“Ob” is a name and “os” is a noun - they look or sound alike but fill different roles in a sentence.

#31,155
“Ob” frequency rank: #2,632
“os” frequency rank: 33787
confusion score

Side-by-Side Comparison

Feature	Ob	os
Definition	Fleuve de Sibérie, qui se jette dans l’océan Arctique.	Élément du squelette des animaux vertébrés, fait de ce tissu dur et calcifié.

Letter map: Ob vs os

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

2 ch

Grammar separator: Ob vs os

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: Ob is aname and osanoun. On the page they differ by a single letter - b in “Ob” becomes s in “os”. Our composite confusion score for this pair is 33787, derived from the frequency rank of both members and their visual similarity.

Ob is recorded at frequency rank #31,155, classified as aname. os is at rank #2,632, tagged as anoun, pronounced \ɔs\.

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 33787, this pair ranks #288,291 of 440,172 scored French 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 name and "os" a noun, so a sentence built for one is usually ungrammatical with the other.

In ordinary French text, does "Ob" or "os" show up more?

"os" is the more common of the two: it sits at frequency rank #2,632 in our French list, against #31,155 for "Ob". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

After this comparison

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

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 #288,291 of 440,172 scored French 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 och". Nearby pair

Confusion rank #288,291 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.