armvsatumWhich spelling fits?

Quick tell: arm is a adjective, atum is a noun, so they fill different roles in a sentence.

Which to use

“arm” is an adjective and “atum” is a noun - they look or sound alike but fill different roles in a sentence.

#27,355
“arm” frequency rank
#16,684
“atum” frequency rank
44039
confusion score

Side-by-Side Comparison

Feature arm atum
Definition pobre peixe da família dos Escombrídeos muito usado na alimentação quer em fresco, quer em conserva

Where the eye mixes arm and atum

Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.

3 ch
arm
4 ch
atum

Visual trap between arm and atum

These two trip readers on the page rather than in the ear: arm is /aʁm/ ouvir^(fonte ?) while atum is /ɐ.ˈtũ/. 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 (adjective vs noun), which is usually the fastest check. Our composite confusion score for this pair is 44039, derived from the frequency rank of both members and their visual similarity.

arm is recorded at frequency rank #27,355, classified as anadj, pronounced /aʁm/ ouvir^(fonte ?). atum is at rank #16,684, tagged as anoun, pronounced /ɐ.ˈtũ/.

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 44039, this pair ranks #21,505 of 75,631 scored Portuguese confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of arm vs atum

Shared letters: am. Private to "arm": r. Private to "atum": tu.

"arm" · 3 letters · shape VCC  ·  "atum" · 4 letters · shape VCVC

Known mistypes of this pair

  • atumatmu · attum · atumm · autm · taum

Frequently Asked Questions

Do "arm" and "atum" mean the same thing in a sentence?
No - they are not even the same part of speech. "arm" is an adjective and "atum" a noun, so a sentence built for one is usually ungrammatical with the other.
Frequency check: "arm" vs "atum" - which ranks higher?
"atum" is the more common of the two: it sits at frequency rank #16,684 in our Portuguese list, against #27,355 for "arm". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

Eye-level mix-up between "arm" and "atum" is sorted above. Next: full entries or other pairs that share a letter shape.

  • Full dictionary entry for "arm" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "atum" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #21,505 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
  • "arm" and "atum" 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 #21,505 of 75,631 scored Portuguese pairs, corpus vintage 2026-09-03, not spelling advice.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list