This is the 2295th most frequent Catalan word.
expulsar
To expel or eject.
The word 'expulsar' here is used to indicate the act of formally removing someone (a student) from an institution or setting due to inappropriate conduct.
El professor va expulsar l'estudiant per mala conducta.
The teacher expelled the student for bad behavior.
In this case, 'expulsar' is applied in a literal sense, describing the physical ejection or release of a substance (smoke).
Van expulsar fum de la màquina per simular un incendi.
Smoke was expelled from the machine to simulate a fire.
Here, 'expulsar' is describing the formal removal of an entity (a sports team) from a competition or activity due to rule violations.