Joist \Joist\ (joist), n. [OE. giste, OF. giste, F. g[^i]te, fr.
   gesir to lie, F. g['e]sir. See {Gist}.] (Arch.)
   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; -- called, according to its position or
   use, {binding joist}, {bridging joist}, {ceiling joist},
   {trimming joist}, etc. See Illust. of {Double-framed floor},
   under {Double}, a.
   
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Binding \Bind"ing\, a.
   That binds; obligatory.
   
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   {Binding beam} (Arch.), the main timber in double flooring.
      

   {Binding joist} (Arch.), the secondary timber in
      double-framed flooring.
      
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   Syn: Obligatory; restraining; restrictive; stringent;
        astringent; costive; styptic.
        
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