"Matter of law" can have different synonyms depending on the context in which it is used. In a legal setting, it can be referred to as a "legal question," which is a specific issue in a case that is decided by the judge based on the law. Another synonym is "issue of law," which is a term used to describe a question of law that must be decided by a judge or jury. In addition, "point of law" is also commonly used to refer to a legal question that must be resolved by a judge. Regardless of the terminology used, all of these synonyms refer to the legal principles and rules that govern the case being heard.