sieurvssinusWhich spelling fits?

Which to use

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

#15,760
“sieur” frequency rank
#26,185
“sinus” frequency rank
41945
confusion score

Side-by-Side Comparison

Feature sieur sinus
Definition Monsieur. Formation anatomique creuse, liquidienne ou pneumatique.

Where the eye mixes sieur and sinus

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

5 ch
sieur
5 ch
sinus

Visual trap between sieur and sinus

A purely visual mix-up. sieur (\sjœʁ\) and sinus (\si.nys\) are said differently, so reading them aloud is the quickest way to catch the wrong one. On the page they stay close: they share most of their letters but differ in 2 positions. Our composite confusion score for this pair is 41945, derived from the frequency rank of both members and their visual similarity.

sieur is recorded at frequency rank #15,760, classified as anoun, pronounced \sjœʁ\. sinus is at rank #26,185, tagged as anoun, pronounced \si.nys\.

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 41945, this pair ranks #229,372 of 440,172 scored French confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of sieur vs sinus

Shared letters: isu. Private to "sieur": er. Private to "sinus": n.

"sieur" · 5 letters · shape CVVVC  ·  "sinus" · 5 letters · shape CVCVC

Known mistypes of this pair

  • sieuriseur · seiur · sieru · sieurr · siuer · ssieur
  • sinusisnus · sinnus · sinsu · sinuss · siuns · snius · ssinus

Frequently Asked Questions

Is swapping "sieur" for "sinus" ever safe?
No. They are said differently (\sjœʁ\ versus \si.nys\) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
Frequency check: "sieur" vs "sinus" - which ranks higher?
"sieur" is the more common of the two: it sits at frequency rank #15,760 in our French list, against #26,185 for "sinus". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.

  • Full dictionary entry for "sieur" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "sinus" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #229,372 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
  • "sieur" and "sinus" also get mixed up with nearby pairs, the highest-scored neighbour is "sinus vs sires". 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 #229,372 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