Which to use
“arco” is a noun and “arm” is an adjective - they look or sound alike but fill different roles in a sentence.
- #4,287
- “arco” frequency rank
- #27,355
- “arm” frequency rank
- 31642
- confusion score
Side-by-Side Comparison
| Feature | arco | arm |
|---|---|---|
| Definition | ente geométrico cuja principal característica é a curva | pobre |
Where the eye mixes arco and arm
Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.
Visual trap between arco and arm
These two trip readers on the page rather than in the ear: arco is /ˈaɾ.ku/ while arm is /aʁm/ ouvir^(fonte ?). Spoken aloud the problem disappears. In writing it persists, because they differ by 1 letter(s) in length, and the parts of speech differ too (noun vs adjective), which is usually the fastest check. Our composite confusion score for this pair is 31642, derived from the frequency rank of both members and their visual similarity.
arco is recorded at frequency rank #4,287, classified as anoun, pronounced /ˈaɾ.ku/. arm is at rank #27,355, tagged as anadj, pronounced /aʁm/ ouvir^(fonte ?).
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 31642, this pair ranks #36,378 of 75,631 scored Portuguese confusable pairs - roughly mid-pack for confusability.
Orthographic DNA of arco vs arm
Shared letters: ar. Private to "arco": co. Private to "arm": m.
"arco" · 4 letters · shape VCCV · "arm" · 3 letters · shape VCC
Known mistypes of this pair
- arco ← arcco · aroc · arrco · raco
Frequently Asked Questions
Is swapping "arco" for "arm" ever safe?
In ordinary Portuguese text, does "arco" or "arm" show up more?
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 "arco" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "arm" - compare definitions side by side with the headword page. Word entry
- This pair ranks #36,378 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
- "arco" and "arm" also get mixed up with nearby pairs, the highest-scored neighbour is "acs vs arm". 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 #36,378 of 75,631 scored Portuguese pairs, corpus vintage 2026-09-03, not spelling advice.