sei
The verdict
“sei” is in the everyday core of Portuguese, ranked #118 in Portuguese word frequency and used as an interjection.
- #118
- frequency rank, Portuguese
- 3
- letters
- 20
- confusable pairs
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - expressa que aquilo ouvido que foi dito ou afirmado por alguém não é tomado como sendo a verdade
Visual similarity to commonly confused words
How many letter changes separate each confused pair (Levenshtein distance, normalized).
Source: PlainSpell confusable corpus (Wiktionary, CC BY-SA).
| Property | Value |
|---|---|
| Headword | sei |
| Language | Portuguese |
| Part of speech | Interjection |
| Letters | 3 |
| Frequency rank | #118 |
| Misspellings tracked | 0 |
| Confusable pairs | 20 |
| Source | Wiktionary (kaikki.org) |
Where “sei” sits in Portuguese frequency
Spelling & Dictionary Insight
The Portuguese entry for sei is 3 letters long, classified as an interjection. Corpus data places it at rank #118 in overall Portuguese word frequency, putting it firmly in the everyday core of the language. The dominant gloss from Wiktionary reads: "expressa que aquilo ouvido que foi dito ou afirmado por alguém não é tomado como sendo a verdade".
sei doesn't appear in our generated misspelling index, and the word's spelling is regular enough that our generator found nothing worth flagging. It also participates in 20 confusable-pair relationships, "só", "si", "su", and more, a pairing that trips writers up because the two words share enough sound or shape to blur together.
This headword's origin isn't recorded in our source data, so its spelling is easiest to reason about phoneme by phoneme, absent a documented history. The correct Portuguese form is sei, spelled S-E-I.
Definition
- 1expressa que aquilo ouvido que foi dito ou afirmado por alguém não é tomado como sendo a verdade
Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA); frequency ordering uses the FrequencyWords open word-frequency list (2018 Portuguese corpus, MIT). See the methodology for how each field is sourced and updated.
Frequently Asked Questions
How do you spell "sei"?
What does "sei" mean?
What words are commonly confused with "sei"?
What language does "sei" come from?
Is PlainSpell free to use?
Using “sei”
The practical upshot for anyone who landed here from a spell-check.
- The one correct Portuguese spelling is S-E-I - every other letter order is a misspelling in standard orthography.
- Don't mix it up with “só” - see the side-by-side comparison. sei vs só
- Browse more Portuguese words and confusable pairs in the same reference. Portuguese words
Data Source
Wiktionary (via kaikki.org), licensed under CC BY-SA & GFDL. Word ordering uses an open word-frequency list; misspelling variants are generated by edit-distance from the correct headword.