sinvssinusTell them apart

Quick tell: sin is a symbol, sinus is a noun, so they fill different roles in a sentence.

Which to use

“sin” is a symbol and “sinus” is a noun - they look or sound alike but fill different roles in a sentence.

#16,237
“sin” frequency rank
#26,185
“sinus” frequency rank
42422
confusion score

Side-by-Side Comparison

Feature sin sinus
Definition Sinus. Formation anatomique creuse, liquidienne ou pneumatique.

Letter map: sin vs sinus

Shared letters muted; letters that set sin and sinus apart highlighted. Shared run: 3.

3 ch
sin
5 ch
sinus

Role in the sentence - sin and sinus

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: sin is asymbol and sinusanoun. On the page they differ by 2 extra letter(s) - “sin” sits inside “sinus”. Our composite confusion score for this pair is 42422, derived from the frequency rank of both members and their visual similarity.

sin is recorded at frequency rank #16,237, classified as asymbol. 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 42422, this pair ranks #225,724 of 440,172 scored French confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of sin vs sinus

Shared letters: ins. Private to "sin": -. Private to "sinus": u.

"sin" · 3 letters · shape CVC  ·  "sinus" · 5 letters · shape CVCVC

Known mistypes of this pair

  • sinusisnus · sinnus · sinsu · sinuss · siuns · snius · ssinus

Frequently Asked Questions

Is swapping "sin" for "sinus" ever safe?
No - they are not even the same part of speech. "sin" is a symbol and "sinus" a noun, so a sentence built for one is usually ungrammatical with the other.
Frequency check: "sin" vs "sinus" - which ranks higher?
"sin" is the more common of the two: it sits at frequency rank #16,237 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.

What to do next

Pair "sin" vs "sinus" is on the table, pick a follow-up below.

  • Full dictionary entry for "sin" 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 #225,724 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
  • "sin" 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 #225,724 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