The term 'Field Arbiter' is a job title that refers to a referee or umpire. The three-letter acronym for this job is 'REF'. Field Arbiters are responsible for making sure that the rules of a game are followed and that the game is played fairly. They also have the authority to make decisions about the outcome of a game, such as awarding penalties or calling a foul. Field Arbiters must be knowledgeable about the rules of the game they are officiating and must be able to make quick decisions in order to keep the game running smoothly.