# sein vs sério

> Portuguese confusable word pair

## The two words

### sein
*verb · IPA /zaɪ̯n/ · frequency rank #43,647*
ser, estar.

### sério
*adjective · IPA /ˈsɛ.ɾju/ · frequency rank #544*
que demonstra profundo pensar

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/pt/vs/sein-vs-serio