Where does “cá voi sát thủ” come from?

cá voi sát thủ (Vietnamese) comes from English killer whale, from Spanish asesina-ballenas.

cá voi sát thủ (Vietnamese): a killer whale

Definitions

Step	Language	Word	Meaning
1	English	killer whale	A sea mammal related to dolphins and porpoises
2	Spanish	asesina-ballenas	—

cá voi sát thủ — Etymology, Origin & Word History | Etymology Explorer