The definition of an exposed beam is a structural support element of a building that is left visible, rather than hidden behind walls or ceilings. Exposed beams are typically made of wood, steel, or concrete, and are often used to create a unique, rustic aesthetic. Exposed beams are often used in the construction of log cabins, barns, and other structures with a more rustic look. They can also be used to create a modern, industrial look in a home or office. Exposed beams are a great way to add character and style to any space, and can be used to create a unique look that stands out from the crowd. They are also a great way to add strength and stability to a structure, and can help to create a sense of open space in a room.