RatvsrustWhich spelling fits?

Which to use

“Rat” and “rust” are a confusable Portuguese pair: similar on the page, but distinct in meaning, check the gloss before you choose.

#37,067
“Rat” frequency rank
#46,045
“rust” frequency rank
83112
confusion score

Side-by-Side Comparison

Feature Rat rust
Definition conselho ferrugem

Where the eye mixes Rat and rust

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

3 ch
Rat
4 ch
rust

Why the eye confuses Rat with rust

A purely visual mix-up. Rat (/raːt/) and rust (/ɹʌst/) are said differently, so reading them aloud is the quickest way to catch the wrong one. On the page they stay close: they differ by 1 letter(s) in length. Our composite confusion score for this pair is 83112, derived from the frequency rank of both members and their visual similarity.

Rat is recorded at frequency rank #37,067, classified as anoun, pronounced /raːt/. 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 83112, this pair ranks #949 of 75,631 scored Portuguese confusable pairs - among the most confusable pairs.

Orthographic DNA of Rat vs rust

Shared letters: rt. Private to "Rat": a. Private to "rust": su.

"Rat" · 3 letters · shape CVC  ·  "rust" · 4 letters · shape CVCC

Known mistypes of this pair

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

Frequently Asked Questions

Can "Rat" and "rust" be used interchangeably?
No. They are said differently (/raːt/ versus /ɹʌst/) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
Which is more common, "Rat" or "rust"?
"Rat" is the more common of the two: it sits at frequency rank #37,067 in our Portuguese list, against #46,045 for "rust". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

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 "Rat" 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 #949 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
  • "Rat" 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 #949 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