bisvsbutWhich spelling fits?

Quick tell: bis is a noun, but is a preposition, so they fill different roles in a sentence.

Which to use

“bis” is a noun and “but” is a preposition - they look or sound alike but fill different roles in a sentence.

#18,497
“bis” frequency rank
#25
“but” frequency rank
18522
confusion score

Side-by-Side Comparison

Feature bis but
Definition plural of bi Apart from, except (for), excluding.

Where the eye mixes bis and but

Muted = shared; highlighted = the visual trap. They share 1 letter in sequence.

3 ch
bis
3 ch
but

Visual trap between bis and but

These two trip readers on the page rather than in the ear: bis is /baɪz/ while but is /ˈbʌt/. Spoken aloud the problem disappears. In writing it persists, because they share most of their letters but differ in 2 positions, and the parts of speech differ too (noun vs preposition), which is usually the fastest check. Our composite confusion score for this pair is 18522, derived from the frequency rank of both members and their visual similarity.

bis is recorded at frequency rank #18,497, classified as anoun, pronounced /baɪz/. but is at rank #25, tagged as aprep, pronounced /ˈbʌt/.

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 18522, this pair ranks #444,315 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of bis vs but

Shared letters: b. Private to "bis": is. Private to "but": tu.

"bis" · 3 letters · shape CVC  ·  "but" · 3 letters · shape CVC

Frequently Asked Questions

Do "bis" and "but" mean the same thing in a sentence?
No - they are not even the same part of speech. "bis" is a noun and "but" a preposition, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "bis" or "but"?
"but" is the more common of the two: it sits at frequency rank #25 in our English list, against #18,497 for "bis". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

What to do next

Visual near-miss handled. Browse the word pages or a neighbour when the next look-alike shows up.

  • Full dictionary entry for "bis" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "but" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #444,315 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "bis" and "but" also get mixed up with nearby pairs, the highest-scored neighbour is "BFS vs bis". Nearby pair

Confusion rank #444,315 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