Which to use
“fœtus” is a noun and “fus” is a verb - they look or sound alike but fill different roles in a sentence.
- #19,296
- “fœtus” frequency rank
- #19,029
- “fus” frequency rank
- 38325
- confusion score
Side-by-Side Comparison
| Feature | fœtus | fus |
|---|---|---|
| Definition | Organisme en voie de développement, chez les animaux vivipares. Il a dépassé le stade d’embryon mais n’est pas encore né. | Première personne du singulier du passé simple de être. |
Where the spellings diverge
Shared letters are muted; the letters that actually set fœtus and fus apart are highlighted. They share 3 letters in sequence, which is exactly why the eye skips the difference.
Spelling & Dictionary Insight
fœtus and fus form a confusable pair in the French index, two distinct headwords that are easily confused because they look alike, sound alike, or both. They differ by 2 letter(s) in length - close enough that the eye skips over the difference, far enough that meaning fully diverges. Our composite confusion score for this pair is 38325, derived from the frequency rank of both members and their visual similarity.
Side-by-side the two words carry different dictionary signatures. fœtus is recorded at frequency rank #19,296, classified as anoun, pronounced \fe.tys\. fus is at rank #19,029, tagged as averb, pronounced \fy\. When the two words belong to different parts of speech, sentence grammar alone usually resolves the confusion; when they share a part of speech, only semantic context separates them, which is why the pair earns a dedicated lookup page.
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. Automated spell-checkers cannot flag confusable substitution because every member of the pair is a valid dictionary word, only the writer, or a grammar/context tool, can confirm that the chosen spelling matches the intended meaning. PlainSpell's confusable index exists precisely to make that contextual choice explicit.
Frequency comparison
Frequently Asked Questions
Can "fœtus" and "fus" be used interchangeably?
Where can I learn more about commonly confused words?
Remembering fœtus vs fus
The fastest way to pick the right one every time.
- Check the role first: if you need a noun, it's “fœtus”; for a verb, it's “fus”.
- See each word in full, definition, IPA, etymology and its other confusables. Full “fœtus” entry
- Browse more pairs most likely to be confused. Most confusable
Nearby confusable pairs
Other commonly confused French word pairs you may also want to compare:
Cite this page
Free to reuse with attribution (CC BY-SA). Copy the citation:
PlainSpell, “fœtus vs fus, French confusable word comparison” (May 6, 2026). Derived from Wiktionary (kaikki.org, CC BY-SA) and an open word-frequency list. https://plainspell.com/fr/vs/f-tus-vs-fus