Wiktionary
prevailing party
n. (context legal English): The party in a civil lawsuit who the factfinder determines to be right, and who, in some jurisdictions, may recover attorney's fees and other expenses associated with the prosecution or defense of the lawsuit.
WordNet
prevailing party
n. the party in a lawsuit who obtains a judgment in their own favor
Usage examples of "prevailing party".
As the terms of communion were insensibly narrowed, and the spiritual authority of the prevailing party was exercised with increasing severity, many of its most respectable adherents, who were called upon to renounce, were provoked to assert their private opinions, to pursue the consequences of their mistaken principles, and openly to erect the standard of rebellion against the unity of the church.