perímetrovsprimeiroConfusable pair

Quick tell: perímetro is a noun, primeiro is an adjective, so they fill different roles in a sentence.

Which to use

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

#8,937
“perímetro” frequency rank
#142
“primeiro” frequency rank
9079
confusion score

Side-by-Side Comparison

Feature perímetro primeiro
Definition soma dos comprimentos de todos os lados de um polígono refere-se àquele que ocupa a posição inicial em uma série; o mais antigo; o que vem antes

Letter map: perímetro vs primeiro

Shared letters muted; letters that set perímetro and primeiro apart highlighted. Shared run: 6. perímetro runs 9 letters (CVCVCVCCV) against primeiro's 8 (CCVCVVCV) - the length gap alone is often enough to separate them once you know to check it.

9 ch
perímetro
8 ch
primeiro

Part-of-speech tell for perímetro / primeiro

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: perímetro is anoun and primeiroanadjective. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 9079, derived from the frequency rank of both members and their visual similarity.

perímetro is recorded at frequency rank #8,937, classified as anoun. primeiro is at rank #142, tagged as anadj, pronounced [pɾi.ˈmej.ɾʊ].

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 9079, this pair ranks #64,476 of 75,631 scored Portuguese confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of perímetro vs primeiro

Shared letters: emopr. Private to "perímetro": tí. Private to "primeiro": i.

"perímetro" · 9 letters · shape CVCVCVCCV  ·  "primeiro" · 8 letters · shape CCVCVVCV

Known mistypes of this pair

  • primeiro ← pirmeiro · pprimeiro · priemiro · primeior · primeirro · primerio · primiero · primmeiro

Frequently Asked Questions

Can "perímetro" and "primeiro" be used interchangeably?
No - they are not even the same part of speech. "perímetro" is a noun and "primeiro" an adjective, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "perímetro" or "primeiro"?
"primeiro" is the more common of the two: it sits at frequency rank #142 in our Portuguese list, against #8,937 for "perímetro". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

Useful next steps

Pair "perímetro" vs "primeiro" is on the table, pick a follow-up below.

  • Full dictionary entry for "perímetro" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "primeiro" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #64,476 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
  • "perímetro" and "primeiro" also get mixed up with nearby pairs, the highest-scored neighbour is "primeira vs primeiro". 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 #64,476 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