In engineering, a stringer is a small, subsidiary beam, joist, or girder. A stringer is connected with, and supported by, other portions of a structure, such as a roof-rafter, floor joist, or the girders or beams of a bridge carrying the rails or roadway and supported in turn by other girders. Research Stringer
In architecture a gain is a square or bevelled notch cut out of a girder, binding joist, or other timber which supports a floor beam, so as to receive the end of the floor beam.
In architecture a joist is a piece of timber laid horizontally, or nearly so, to which the planks of the floor, or the laths or furring strips of a ceiling, are nailed. The joints are called varying names according to their position or use, a binding joist, bridging joist, ceiling joist, trimming
joist, etc. In floors constructed without girders there is usually but one thickness of joists, to the underside of which the ceiling is attached, but when girders are used they are often double, (the upper row carrying the flooring, and the lower the ceiling,) with a series of larger timbers between them, called binding Joists, When this kind of construction, is used the upper joists are called bridging joists. Research Joist