oncevsondeWhich spelling fits?

Which to use

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

#11,815
“once” frequency rank
#6,324
“onde” frequency rank
18139
confusion score

Side-by-Side Comparison

Feature once onde
Definition Unité de mesure de la masse (système impérial britannique avoirdupois), qui vaut 28,3495231 grammes pour l'once commune → voir ounce. Ses symboles sont oz et ℥. L'once troy (troy ounce) équivaut pour sa part à 31,1034768 grammes. Ondulations d’un milieu élastique ou d’un flux électromagnétique. Perturbation d’un milieu qui se propage.

Where the eye mixes once and onde

Muted = shared; highlighted = the visual trap. They share 3 letters in sequence.

4 ch
once
4 ch
onde

Look-alike desk: once vs onde

A purely visual mix-up. once (\ɔ̃s\) and onde (\ɔ̃d\) 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 - c in “once” becomes d in “onde”. Our composite confusion score for this pair is 18139, derived from the frequency rank of both members and their visual similarity.

once is recorded at frequency rank #11,815, classified as anoun, pronounced \ɔ̃s\. onde is at rank #6,324, tagged as anoun, pronounced \ɔ̃d\.

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 18139, this pair ranks #379,800 of 440,172 scored French confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of once vs onde

Shared letters: eno. Private to "once": c. Private to "onde": d.

"once" · 4 letters · shape VCCV  ·  "onde" · 4 letters · shape VCCV

Known mistypes of this pair

  • onceocne · oncce · onec · onnce
  • ondenode · odne · ondde · oned · onnde

Frequently Asked Questions

Do "once" and "onde" mean the same thing in a sentence?
No. They are said differently (\ɔ̃s\ versus \ɔ̃d\) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
Which is more common, "once" or "onde"?
"onde" is the more common of the two: it sits at frequency rank #6,324 in our French list, against #11,815 for "once". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

Eye-level mix-up between "once" and "onde" is sorted above. Next: full entries or other pairs that share a letter shape.

  • Full dictionary entry for "once" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "onde" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #379,800 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
  • "once" and "onde" also get mixed up with nearby pairs, the highest-scored neighbour is "och vs once". 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 #379,800 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