Which to use
“Petr” is a name and “Petrus” is a noun - they look or sound alike but fill different roles in a sentence.
- #39,455
- “Petr” frequency rank
- #40,419
- “Petrus” frequency rank
- 79874
- confusion score
Side-by-Side Comparison
| Feature | Petr | Petrus |
|---|---|---|
| Definition | Prénom tchèque, équivalent de Pierre. | Pierre. |
Letter map: Petr vs Petrus
Shared letters muted; letters that set Petr and Petrus apart highlighted. Shared run: 4. Petr runs 4 letters (CVCC) against Petrus's 6 (CVCCVC) - the length gap alone is often enough to separate them once you know to check it.
Role in the sentence - Petr and Petrus
Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: Petr is aname and Petrusanoun. On the page they differ by 2 extra letter(s) - “Petr” sits inside “Petrus”. Our composite confusion score for this pair is 79874, derived from the frequency rank of both members and their visual similarity.
Petr is recorded at frequency rank #39,455, classified as aname, pronounced \pɛtr̩\. Petrus is at rank #40,419, tagged as anoun.
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 79874, this pair ranks #22,268 of 440,172 scored French confusable pairs - among the most confusable pairs.
Orthographic DNA of Petr vs Petrus
Shared letters: eprt. Private to "Petr": -. Private to "Petrus": su.
"Petr" · 4 letters · shape CVCC · "Petrus" · 6 letters · shape CVCCVC
Known mistypes of this pair
Frequently Asked Questions
Is swapping "Petr" for "Petrus" ever safe?
Which is more common, "Petr" or "Petrus"?
Useful next steps
Pair "Petr" vs "Petrus" is on the table, pick a follow-up below.
- Full dictionary entry for "Petr" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "Petrus" - compare definitions side by side with the headword page. Word entry
- This pair ranks #22,268 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
- "Petr" and "Petrus" also get mixed up with nearby pairs, the highest-scored neighbour is "peep vs Petr". 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 #22,268 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.