The term 'Bridge Supporter' is a job description for someone who builds and maintains trestles, which are structures that support bridges. A TRESTLE is a type of bridge support consisting of a framework of beams or posts that form a vertical frame to support a bridge deck. Trestles are typically made of wood, steel, or concrete and are used to support the weight of a bridge and its load. They are also used to provide stability and reduce vibration. Bridge supporters are responsible for constructing and maintaining these trestles, ensuring that they are safe and secure.