Which to use
“semi” is a verb and “si” is a pronoun - they look or sound alike but fill different roles in a sentence.
- #4,431
- “semi” frequency rank
- #482
- “si” frequency rank
- 4913
- confusion score
Side-by-Side Comparison
| Feature | semi | si |
|---|---|---|
| Definition | semear, plantar | refere-se à terceira pessoa, indica reflexividade e é usado após preposição (a, de, em, contra, sobre, por, etc., exceto com) |
Where the eye mixes semi and si
Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.
Why the eye confuses semi with si
These two trip readers on the page rather than in the ear: semi is /ˈsɛ.mi/. while si is /ˈsi/. Spoken aloud the problem disappears. In writing it persists, because they differ by 2 letter(s) in length, and the parts of speech differ too (verb vs pronoun), which is usually the fastest check. Our composite confusion score for this pair is 4913, derived from the frequency rank of both members and their visual similarity.
semi is recorded at frequency rank #4,431, classified as averb, pronounced /ˈsɛ.mi/.. si is at rank #482, tagged as apron, pronounced /ˈsi/.
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 4913, this pair ranks #69,825 of 75,631 scored Portuguese confusable pairs - a relatively easy-to-tell-apart pair.
Orthographic DNA of semi vs si
Shared letters: is. Private to "semi": em. Private to "si": -.
"semi" · 4 letters · shape CVCV · "si" · 2 letters · shape CV
Known mistypes of this pair
- semi ← esmi · seim · semmi · smei · ssemi
Frequently Asked Questions
Do "semi" and "si" mean the same thing in a sentence?
Frequency check: "semi" vs "si" - which ranks higher?
After this comparison
Visual near-miss handled. Browse the word pages or a neighbour when the next look-alike shows up.
- Full dictionary entry for "semi" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "si" - compare definitions side by side with the headword page. Word entry
- This pair ranks #69,825 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
- "semi" and "si" also get mixed up with nearby pairs, the highest-scored neighbour is "semi vs seno". 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 #69,825 of 75,631 scored Portuguese pairs, corpus vintage 2026-09-03, not spelling advice.