|1.||See also rolled-steel joist a beam made of timber, steel, or reinforced concrete, used in the construction of floors, roofs, etc|
|2.||(tr) to construct (a floor, roof, etc) with joists|
|[C14: from Old French giste beam supporting a bridge, from Vulgar Latin jacitum (unattested) support, from jacēre to lie]|
ceiling or floor support in building construction. Joists-of timber, steel, or reinforced concrete-are laid in a parallel series across or abutting girders or a bearing wall, to which they are attached, usually by metal supports called joist hangers, or anchors
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