smutvssudTell them apart

Which to use

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

#34,290
“smut” frequency rank
#37,717
“sud” frequency rank
72007
confusion score

Side-by-Side Comparison

Feature smut sud
Definition Soot. A bubble of lather or foam (the singular of suds).

Where the eye mixes smut and sud

Muted = shared; highlighted = the visual trap. They share 2 letters in sequence. smut runs 4 letters (CCVC) against sud's 3 (CVC) - the length gap alone is often enough to separate them once you know to check it.

4 ch
smut
3 ch
sud

Visual trap between smut and sud

A purely visual mix-up. smut (/smʌt/) and sud (/sʌd/) 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 72007, derived from the frequency rank of both members and their visual similarity.

smut is recorded at frequency rank #34,290, classified as anoun, pronounced /smʌt/. sud is at rank #37,717, tagged as anoun, pronounced /sʌd/.

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 72007, this pair ranks #44,565 of 530,003 scored English confusable pairs - among the most confusable pairs.

Orthographic DNA of smut vs sud

Shared letters: su. Private to "smut": mt. Private to "sud": d.

"smut" · 4 letters · shape CCVC  ·  "sud" · 3 letters · shape CVC

Known mistypes of this pair

  • smutsmmut · smtu · smutt · ssmut · sumt

Frequently Asked Questions

Can "smut" and "sud" be used interchangeably?
No. They are said differently (/smʌt/ versus /sʌd/) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
In ordinary English text, does "smut" or "sud" show up more?
"smut" is the more common of the two: it sits at frequency rank #34,290 in our English list, against #37,717 for "sud". 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 "smut" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "sud" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #44,565 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "smut" and "sud" also get mixed up with nearby pairs, the highest-scored neighbour is "sud vs sura". 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 #44,565 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