cause of action
1: the grounds (as violation of a right) that entitle a plaintiff to bring a suit
an amended pleading reiterating a cause of action for lost profits — J. H. Friedenthal et al.; also: the part of a suit brought on those grounds
removed the cause of action to the district court
2: right of action (1)
the court, led by Justice Brennan, said Congress intended to provide a private cause of action — National Law Journal
Merriam-Webster’s Dictionary of Law. Merriam-Webster. 1996.