Which to use
“sein” is a verb and “sem” is a preposition - they look or sound alike but fill different roles in a sentence.
- #43,647
- “sein” frequency rank
- #69
- “sem” frequency rank
- 43716
- confusion score
Side-by-Side Comparison
| Feature | sein | sem |
|---|---|---|
| Definition | ser, estar. | indicativa de carência ou ausência |
Where the eye mixes sein and sem
Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.
Look-alike desk: sein vs sem
These two trip readers on the page rather than in the ear: sein is /zaɪ̯n/ while sem is /sɐ̃j̃/. 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 (verb vs preposition), which is usually the fastest check. Our composite confusion score for this pair is 43716, derived from the frequency rank of both members and their visual similarity.
sein is recorded at frequency rank #43,647, classified as averb, pronounced /zaɪ̯n/. sem is at rank #69, tagged as aprep, pronounced /sɐ̃j̃/.
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 43716, this pair ranks #21,903 of 75,631 scored Portuguese confusable pairs - roughly mid-pack for confusability.
Orthographic DNA of sein vs sem
Shared letters: es. Private to "sein": in. Private to "sem": m.
"sein" · 4 letters · shape CVVC · "sem" · 3 letters · shape CVC
Known mistypes of this pair
- sein ← esin · seinn · seni · sien · ssein
Frequently Asked Questions
Is swapping "sein" for "sem" ever safe?
Frequency check: "sein" vs "sem" - which ranks higher?
What to do next
Visual near-miss handled. Browse the word pages or a neighbour when the next look-alike shows up.
- Full dictionary entry for "sein" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "sem" - compare definitions side by side with the headword page. Word entry
- This pair ranks #21,903 of 75,631 scored Portuguese confusable pairs in this corpus vintage. Corpus statistics
- "sein" and "sem" also get mixed up with nearby pairs, the highest-scored neighbour is "sein vs slip". 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 #21,903 of 75,631 scored Portuguese pairs, corpus vintage 2026-09-03, not spelling advice.