altérervsalternerWhich spelling fits?

Which to use

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

#22,157
“altérer” frequency rank
#30,458
“alterner” frequency rank
52615
confusion score

Side-by-Side Comparison

Feature altérer alterner
Definition Modifier dans sa nature, dans sa structure, un corps. Faire successivement et tour à tour une même chose en parlant de deux personnes.

Where the eye mixes altérer and alterner

Muted = shared; highlighted = the visual trap. They share 6 letters in sequence. altérer runs 7 letters (VCCVCVC) against alterner's 8 (VCCVCCVC) - the length gap alone is often enough to separate them once you know to check it.

7 ch
altérer
8 ch
alterner

Why the eye confuses altérer with alterner

A purely visual mix-up. altérer (\al.te.ʁe\) and alterner (\al.tɛʁ.ne\) 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 1 letter(s) in length. Our composite confusion score for this pair is 52615, derived from the frequency rank of both members and their visual similarity.

altérer is recorded at frequency rank #22,157, classified as averb, pronounced \al.te.ʁe\. alterner is at rank #30,458, tagged as averb, pronounced \al.tɛʁ.ne\.

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 52615, this pair ranks #146,463 of 440,172 scored French confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of altérer vs alterner

Shared letters: aelrt. Private to "altérer": é. Private to "alterner": n.

"altérer" · 7 letters · shape VCCVCVC  ·  "alterner" · 8 letters · shape VCCVCCVC

Known mistypes of this pair

  • alterner ← aletrner · allterner · altenrer · alterenr · alternerr · alternner · alternre · alterrner

Frequently Asked Questions

Is swapping "altérer" for "alterner" ever safe?
No. They are said differently (\al.te.ʁe\ versus \al.tɛʁ.ne\) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
In ordinary French text, does "altérer" or "alterner" show up more?
"altérer" is the more common of the two: it sits at frequency rank #22,157 in our French list, against #30,458 for "alterner". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

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

  • Full dictionary entry for "altérer" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "alterner" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #146,463 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
  • "altérer" and "alterner" also get mixed up with nearby pairs, the highest-scored neighbour is "aliéner vs alterner". 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 #146,463 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