ruavsrustConfusable pair

Quick tell: rua is a intj, rust is a noun, so they fill different roles in a sentence.

Which to use

“rua” is an intj and “rust” is a noun - they look or sound alike but fill different roles in a sentence.

#420
“rua” frequency rank
#46,045
“rust” frequency rank
46465
confusion score

Side-by-Side Comparison

Feature rua rust
Definition fora!, gire! - ordem enérgica para deixar o recinto onde se está ferrugem

Where the eye mixes rua and rust

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

3 ch
rua
4 ch
rust

Visual trap between rua and rust

These two trip readers on the page rather than in the ear: rua is /ˈRuɐ/ while rust is /ɹʌst/. 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 (intj vs noun), which is usually the fastest check. Our composite confusion score for this pair is 46465, derived from the frequency rank of both members and their visual similarity.

rua is recorded at frequency rank #420, classified as anintj, pronounced /ˈRuɐ/. rust is at rank #46,045, tagged as anoun, pronounced /ɹʌst/.

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 46465, this pair ranks #18,831 of 75,631 scored Portuguese confusable pairs - among the most confusable pairs.

Orthographic DNA of rua vs rust

Shared letters: ru. Private to "rua": a. Private to "rust": st.

"rua" · 3 letters · shape CVV  ·  "rust" · 4 letters · shape CVCC

Known mistypes of this pair

  • rustrrust · rsut · russt · rustt · ruts · urst

Frequently Asked Questions

Is swapping "rua" for "rust" ever safe?
No - they are not even the same part of speech. "rua" is an intj and "rust" a noun, so a sentence built for one is usually ungrammatical with the other.
In ordinary Portuguese text, does "rua" or "rust" show up more?
"rua" is the more common of the two: it sits at frequency rank #420 in our Portuguese list, against #46,045 for "rust". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

After this comparison

Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.

  • Full dictionary entry for "rua" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "rust" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #18,831 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
  • "rua" and "rust" also get mixed up with nearby pairs, the highest-scored neighbour is "ruma vs rust". 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 #18,831 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