Gemel hinge

from The Collaborative International Dictionary of English v.0.48

Gemel \Gem"el\, n.
   1. One of the twins. [Obs.] --Wyclif.
      [1913 Webster]

   2. (Heb.) One of the barrulets placed parallel and closed to
      each other. Cf. {Bars gemel}, under {Gemel}, a.
      [1913 Webster]

            Two gemels silver between two griffins passant.
                                                  --Strype.
      [1913 Webster]

   {Gemel hinge} (Locksmithing), a hinge consisting of an eye or
      loop and a hook.

   {Gemel ring}, a ring with two or more links; a gimbal. See
      {Gimbal}.

   {Gemel window}, a window with two bays.
      [1913 Webster]