dud vs dun, What's the Difference?

Which to use

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

#29,251
“dud” frequency rank: #18,810
“dun” frequency rank: 48061
confusion score

Side-by-Side Comparison

Feature	dud	dun
Definition	A device or machine that is useless because it does not work properly or has failed to work, such as a bomb, or explosive projectile.	A brownish grey colour.

Where the eye mixes dud and dun

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

3 ch

dud

3 ch

dun

Visual trap between dud and dun

A purely visual mix-up. dud (/dʌd/) and dun (/dʌn/) 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 a single letter - d in “dud” becomes n in “dun”. Our composite confusion score for this pair is 48061, derived from the frequency rank of both members and their visual similarity.

dud is recorded at frequency rank #29,251, classified as anoun, pronounced /dʌd/. dun is at rank #18,810, tagged as anoun, pronounced /dʌn/.

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 48061, this pair ranks #196,660 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of dud vs dun

Shared letters: du. Private to "dud": -. Private to "dun": n.

"dud" · 3 letters · shape CVC · "dun" · 3 letters · shape CVC

Frequently Asked Questions

Can "dud" and "dun" be used interchangeably?

No. They are said differently (/dʌd/ versus /dʌn/) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.

Frequency check: "dud" vs "dun" - which ranks higher?

"dun" is the more common of the two: it sits at frequency rank #18,810 in our English list, against #29,251 for "dud". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Useful next steps

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

Full dictionary entry for "dud" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "dun" - compare definitions side by side with the headword page. Word entry
This pair ranks #196,660 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
"dud" and "dun" also get mixed up with nearby pairs, the highest-scored neighbour is "dox vs dud". Nearby pair

Confusion rank #196,660 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.