Main Entry:

joist

Pronunciation:

\ˈjȯist\

Function:

noun

Etymology:

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

Date:

15th century

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

[joist illustration]