bleuvsbuWhich spelling fits?

Which to use

“bleu” and “bu” are a confusable French pair: similar on the page, but distinct in meaning, check the gloss before you choose.

#1,470
“bleu” frequency rank
#5,636
“bu” frequency rank
7106
confusion score

Side-by-Side Comparison

Feature bleu bu
Definition De la couleur du ciel en plein jour quand il est dégagé. #0000FF Absorbé, en parlant d’un liquide ou de sentiment (les sentiments étaient autrefois considérés comme des humeurs, au sens propre de quelque chose d’humide).

Letter map: bleu vs bu

Shared letters muted; letters that set bleu and bu apart highlighted. Shared run: 2.

4 ch
bleu
2 ch
bu

Corpus notes: bleu and bu

bleu and bu are indexed as a confusable French pair. We have no recorded pronunciation or part of speech for both members, so the spelling overlap is what we can show you: they differ by 2 letter(s) in length. Our composite confusion score for this pair is 7106, derived from the frequency rank of both members and their visual similarity.

bleu is recorded at frequency rank #1,470, classified as anadj, pronounced \blø\. bu is at rank #5,636, tagged as anadj.

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 7106, this pair ranks #424,217 of 440,172 scored French confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of bleu vs bu

Shared letters: bu. Private to "bleu": el. Private to "bu": -.

"bleu" · 4 letters · shape CCVV  ·  "bu" · 2 letters · shape CV

Known mistypes of this pair

  • bleubbleu · belu · blleu · lbeu

Frequently Asked Questions

Can "bleu" and "bu" be used interchangeably?
No. They differ by 2 letter(s) in length, but the dictionary glosses above give them different meanings, so swapping one for the other changes what the sentence says.
Frequency check: "bleu" vs "bu" - which ranks higher?
"bleu" is the more common of the two: it sits at frequency rank #1,470 in our French list, against #5,636 for "bu". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

Pair "bleu" vs "bu" is on the table, pick a follow-up below.

  • Full dictionary entry for "bleu" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "bu" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #424,217 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
  • "bleu" and "bu" also get mixed up with nearby pairs, the highest-scored neighbour is "bu vs bury". 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 #424,217 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list