punvspusWhich spelling fits?

Quick tell: pun is a verb, pus is a noun, so they fill different roles in a sentence.

Which to use

“pun” is a verb and “pus” is a noun - they look or sound alike but fill different roles in a sentence.

#13,993
“pun” frequency rank
#28,336
“pus” frequency rank
42329
confusion score

Side-by-Side Comparison

Feature pun pus
Definition To beat; strike with force; to ram; to pound, as in a mortar; reduce to powder, to pulverize. A whitish-yellow or yellow substance composed primarily of dead white blood cells and dead pyogenic bacteria, normally found in regions of bacterial infection.

Where the eye mixes pun and pus

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

3 ch
pun
3 ch
pus

Why the eye confuses pun with pus

These two trip readers on the page rather than in the ear: pun is /pʌn/ while pus is /pʌs/. Spoken aloud the problem disappears. In writing it persists, because they differ by a single letter - n in “pun” becomes s in “pus”, and the parts of speech differ too (verb vs noun), which is usually the fastest check. Our composite confusion score for this pair is 42329, derived from the frequency rank of both members and their visual similarity.

pun is recorded at frequency rank #13,993, classified as averb, pronounced /pʌn/. pus is at rank #28,336, tagged as anoun, pronounced /pʌs/.

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 42329, this pair ranks #250,226 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of pun vs pus

Shared letters: pu. Private to "pun": n. Private to "pus": s.

"pun" · 3 letters · shape CVC  ·  "pus" · 3 letters · shape CVC

Frequently Asked Questions

Is swapping "pun" for "pus" ever safe?
No - they are not even the same part of speech. "pun" is a verb and "pus" a noun, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "pun" or "pus"?
"pun" is the more common of the two: it sits at frequency rank #13,993 in our English list, against #28,336 for "pus". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

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

  • Full dictionary entry for "pun" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "pus" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #250,226 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "pun" and "pus" also get mixed up with nearby pairs, the highest-scored neighbour is "PPA vs pus". Nearby pair

Confusion rank #250,226 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