class-action suit vs causa

class-action suit and causa both are nouns.

Word	Noun	Adjective	Verb	Adverb
class-action suit	Yes	No	No	No
causa	Yes	No	No	No

As nouns, causa is a hypernym of class-action suit; that is, causa is a word with a broader meaning than class-action suit:

class-action suit: a lawsuit brought by a representative member of a large group of people on behalf of all members of the group
causa: a comprehensive term for any proceeding in a court of law whereby an individual seeks a legal remedy

Other hypernyms of class-action suit include case, cause, lawsuit, suit.

class-action suit (noun)	causa (noun)
a lawsuit brought by a representative member of a large group of people on behalf of all members of the group	a comprehensive term for any proceeding in a court of law whereby an individual seeks a legal remedy