An ARBITER is a person who makes decisions in a dispute, often as a mediator. A BOSS is someone who has authority over others and makes decisions for them. A JUDGE is a person who presides over a court of law and makes decisions based on the evidence presented. A determiner is someone who makes a decision based on facts or evidence. A chooser is someone who makes a decision by selecting from a range of options. All of these terms refer to a decision maker, someone who is responsible for making decisions.