What does the term "soffit" refer to in building construction?

The term "soffit" specifically refers to the underside of an overhanging part or member of a building, such as eaves, arches, or balconies. In building construction, the soffit serves both aesthetic and functional purposes. Aesthetically, it provides a finished look to the structure, while functionally, it can aid in ventilation and serve to conceal structural elements like beams or ductwork.

Other options do not accurately define "soffit." For instance, a structural pillar supporting the roof pertains to a different component of the building, while the exterior wall refers to the vertical boundary of a building, not the underside of an overhanging structure. Lastly, roofing material types do not relate to the soffit either as they describe the top surface of a building rather than its underbelly.