the timber, metallic, or concrete beams set parallel from wall to wall or across or abutting girders to aid a floor or roof.
some timber laid horizontally, or almost so, to which the planks of the flooring, or even the laths or furring strips of a ceiling, tend to be nailed. Known as, according to its place or use, binding joist, bridging joist, ceiling joist, cutting joist, etc.
some timber set horizontally, or almost so, that the planks associated with floor, or even the laths or furring pieces of a ceiling, are nailed; -- known as, according to its position or use, binding joist, bridging joist, ceiling joist, trimming joist, etc. See Illust. of Double-framed floor, under two fold, a.
In building, one of the pieces of timber that the boards of a floor and/or laths of a ceiling are nailed, and which by themselves rest regarding the walls or on girders, and sometimes on both. Joists tend to be laid horizontally in synchronous equidistant rows.