This is the 6476th most frequent Catalan word.
per
"For" or "by."
The word 'per' is used to indicate the recipient of the action, equivalent to 'for' in English.
Vaig comprar un llibre per a la meva germana.
I bought a book for my sister.
The word 'per' is used as part of the interrogative phrase 'per què', which means 'why', indicating the reason or cause.
Per què vas fer aquesta pregunta?
Why did you ask that question?
The word 'per' indicates passage through a place, equivalent to 'through' or 'via' in English.