Which to use
“duff” is a noun and “dum” is an adjective - they look or sound alike but fill different roles in a sentence.
- #18,063
- “duff” frequency rank
- #23,517
- “dum” frequency rank
- 41580
- confusion score
Side-by-Side Comparison
| Feature | duff | dum |
|---|---|---|
| Definition | Dough. | cooked with steam |
Where the eye mixes duff and dum
Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.
Visual trap between duff and dum
These two trip readers on the page rather than in the ear: duff is /dʌf/ while dum is /dʌm/. 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 (noun vs adjective), which is usually the fastest check. Our composite confusion score for this pair is 41580, derived from the frequency rank of both members and their visual similarity.
duff is recorded at frequency rank #18,063, classified as anoun, pronounced /dʌf/. dum is at rank #23,517, tagged as anadj, pronounced /dʌm/.
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 41580, this pair ranks #257,002 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.
Orthographic DNA of duff vs dum
Shared letters: du. Private to "duff": f. Private to "dum": m.
"duff" · 4 letters · shape CVCC · "dum" · 3 letters · shape CVC
Known mistypes of this pair
- duff ← dduff · dfuf · duf · udff
Frequently Asked Questions
Do "duff" and "dum" mean the same thing in a sentence?
Frequency check: "duff" vs "dum" - which ranks higher?
After this comparison
Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.
- Full dictionary entry for "duff" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "dum" - compare definitions side by side with the headword page. Word entry
- This pair ranks #257,002 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
- "duff" and "dum" also get mixed up with nearby pairs, the highest-scored neighbour is "dox vs dum". 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 #257,002 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.