The term 'Belt Tightener' can be summarized as a job that involves tightening belts. A belt tightener is a person who is responsible for tightening and adjusting the tension of belts in order to ensure that they are properly functioning. The term 'GUT' is a three letter acronym which stands for 'General Utility Technician'. This job title is often used to describe someone who is responsible for performing a variety of tasks related to maintenance and repair.