runsvsrustTell them apart

Which to use

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

#1,535
“runs” frequency rank
#10,604
“rust” frequency rank
12139
confusion score

Side-by-Side Comparison

Feature runs rust
Definition plural of run The deteriorated state of iron or steel as a result of moisture and oxidation; it consists mostly of iron(III) oxide (ferric oxide) and iron(II) oxide (ferrous oxide).

Where the eye mixes runs and rust

Muted = shared; highlighted = the visual trap. They share 3 letters in sequence.

4 ch
runs
4 ch
rust

Look-alike desk: runs vs rust

A purely visual mix-up. runs (/ɹʌnz/) 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 share most of their letters but differ in 2 positions. Our composite confusion score for this pair is 12139, derived from the frequency rank of both members and their visual similarity.

runs is recorded at frequency rank #1,535, classified as anoun, pronounced /ɹʌnz/. rust is at rank #10,604, 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 12139, this pair ranks #483,215 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of runs vs rust

Shared letters: rsu. Private to "runs": n. Private to "rust": t.

"runs" · 4 letters · shape CVCC  ·  "rust" · 4 letters · shape CVCC

Known mistypes of this pair

  • runsrnus · rruns · runns · runss · rusn · urns
  • rustrrust · rsut · russt · rustt · ruts · urst

Frequently Asked Questions

Can "runs" and "rust" be used interchangeably?
No. They are said differently (/ɹʌnz/ versus /ɹʌst/) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
In ordinary English text, does "runs" or "rust" show up more?
"runs" is the more common of the two: it sits at frequency rank #1,535 in our English list, against #10,604 for "rust". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

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

  • Full dictionary entry for "runs" 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 #483,215 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "runs" and "rust" also get mixed up with nearby pairs, the highest-scored neighbour is "Rua 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 #483,215 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.

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

Source: FrequencyWords open word-frequency list