To make the subject of a lawsuit; to contest in law; to prosecute or defend by pleadings, exhibition of evidence, and judicial debate in a court; as, to litigate a cause.
To carry on a legal contest by a judicial process. For example, employers will often go to the courts (litigate) to appeal a decision by theĀ National Labor Relations Board.
institute legal proceedings against; file a suit against; "He was warned that the district attorney would process him"; "She actioned the company for discrimination"