radonvsrançonTell them apart

Which to use

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

#44,667
“radon” frequency rank
#14,545
“rançon” frequency rank
59212
confusion score

Side-by-Side Comparison

Feature radon rançon
Definition Élément chimique de numéro atomique 86 et de symbole Rn qui fait partie de la série chimique des gaz rares. Prix exigé pour la délivrance d’un captif ou d’un prisonnier de guerre, ou pour relâcher un vaisseau de guerre, ou débloquer un système informatique piraté, etc.

Where the eye mixes radon and rançon

Muted = shared; highlighted = the visual trap. They share 4 letters in sequence.

5 ch
radon
6 ch
rançon

Visual trap between radon and rançon

A purely visual mix-up. radon (\ʁa.dɔ̃\) and rançon (\ʁɑ̃.sɔ̃\) 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 59212, derived from the frequency rank of both members and their visual similarity.

radon is recorded at frequency rank #44,667, classified as anoun, pronounced \ʁa.dɔ̃\. rançon is at rank #14,545, tagged as anoun, pronounced \ʁɑ̃.sɔ̃\.

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 59212, this pair ranks #104,437 of 440,172 scored French confusable pairs - among the most confusable pairs.

Orthographic DNA of radon vs rançon

Shared letters: anor. Private to "radon": d. Private to "rançon": ç.

"radon" · 5 letters · shape CVCVC  ·  "rançon" · 6 letters · shape CVCCVC

Known mistypes of this pair

  • radonardon · raddon · radonn · raodn · rdaon · rradon

Frequently Asked Questions

Do "radon" and "rançon" mean the same thing in a sentence?
No. They are said differently (\ʁa.dɔ̃\ versus \ʁɑ̃.sɔ̃\) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
Which is more common, "radon" or "rançon"?
"rançon" is the more common of the two: it sits at frequency rank #14,545 in our French list, against #44,667 for "radon". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

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 "radon" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "rançon" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #104,437 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
  • "radon" and "rançon" also get mixed up with nearby pairs, the highest-scored neighbour is "radon vs ramen". 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 #104,437 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