Dictionary

joist

noun \ˈjȯist\

: a strong, heavy board that supports a floor or ceiling

Full Definition of JOIST

: any of the small timbers or metal beams ranged parallel from wall to wall in a structure to support a floor or ceiling

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Middle English giste, joiste, from Anglo-French giste, from Vulgar Latin *jacitum, from Latin jacēre to lie — more at adjacent

First Known Use: 15th century

JOIST Defined for Kids

noun \ˈjȯist\

: any of the small timbers or metal beams laid crosswise in a building to support a floor or ceiling

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