Which to use
“si” is a pronoun and “sun” is a noun - they look or sound alike but fill different roles in a sentence.
- #482
- “si” frequency rank
- #7,698
- “sun” frequency rank
- 8180
- confusion score
Side-by-Side Comparison
| Feature | si | sun |
|---|---|---|
| Definition | refere-se à terceira pessoa, indica reflexividade e é usado após preposição (a, de, em, contra, sobre, por, etc., exceto com) | Sol |
Where the eye mixes si and sun
Muted = shared; highlighted = the visual trap. They share 1 letter in sequence.
Why the eye confuses si with sun
These two trip readers on the page rather than in the ear: si is /ˈsi/ while sun is /sʌn/. Spoken aloud the problem disappears. In writing it persists, because they differ by 1 letter(s) in length, and the parts of speech differ too (pronoun vs noun), which is usually the fastest check. Our composite confusion score for this pair is 8180, derived from the frequency rank of both members and their visual similarity.
si is recorded at frequency rank #482, classified as apron, pronounced /ˈsi/. sun is at rank #7,698, tagged as anoun, pronounced /sʌn/.
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 8180, this pair ranks #65,692 of 75,631 scored Portuguese confusable pairs - a relatively easy-to-tell-apart pair.
Orthographic DNA of si vs sun
Shared letters: s. Private to "si": i. Private to "sun": nu.
"si" · 2 letters · shape CV · "sun" · 3 letters · shape CVC
Frequently Asked Questions
Do "si" and "sun" mean the same thing in a sentence?
Which is more common, "si" or "sun"?
What to do next
Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.
- Full dictionary entry for "si" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "sun" - compare definitions side by side with the headword page. Word entry
- This pair ranks #65,692 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
- "si" and "sun" also get mixed up with nearby pairs, the highest-scored neighbour is "sueño vs sun". Nearby pair
Confusion rank #65,692 of 75,631 scored Portuguese pairs, corpus vintage 2026-09-03, not spelling advice.