Which to use
“sigma” is a noun and “signa” is a verb - they look or sound alike but fill different roles in a sentence.
- #31,736
- “sigma” frequency rank
- #30,371
- “signa” frequency rank
- 62107
- confusion score
Side-by-Side Comparison
| Feature | sigma | signa |
|---|---|---|
| Definition | σ, ς, Σ, dix-huitième lettre et treizième consonne de l’alphabet grec. | Troisième personne du singulier du passé simple de signer. |
Where the spellings diverge
Shared letters are muted; the letters that actually set sigma and signa apart are highlighted. They share 4 letters in sequence, which is exactly why the eye skips the difference.
Spelling & Dictionary Insight
These two trip readers on the page rather than in the ear: sigma is \siɡ.ma\ while signa is \si.ɲa\. Spoken aloud the problem disappears. In writing it persists, because they differ by a single letter - m in “sigma” becomes n in “signa”, and the parts of speech differ too (noun vs verb), which is usually the fastest check. Our composite confusion score for this pair is 62107, derived from the frequency rank of both members and their visual similarity.
sigma is recorded at frequency rank #31,736, classified as anoun, pronounced \siɡ.ma\. signa is at rank #30,371, tagged as averb, pronounced \si.ɲa\.
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 62107, this pair ranks #88,794 of 440,172 scored French confusable pairs - among the most confusable pairs.
Orthographic DNA of sigma vs signa
Shared letters: agis. Private to "sigma": m. Private to "signa": n.
"sigma" · 5 letters · shape CVCCV · "signa" · 5 letters · shape CVCCV
Known mistypes of this pair
Frequency comparison
Frequently Asked Questions
Can "sigma" and "signa" be used interchangeably?
Which is more common, "sigma" or "signa"?
Remembering sigma vs signa
The fastest way to pick the right one every time.
- Check the role first: if you need a noun, it's “sigma”; for a verb, it's “signa”.
- See each word in full, definition, IPA, etymology and its other confusables. Full “sigma” entry
- Browse more pairs most likely to be confused. Most confusable