Source : Webster's Revised Unabridged Dictionary (1913)

Tregetour \Treg"et*our\, n. [OE. tresgeteor. See {Trans-}, and
   {Jet} a shooting forth.]
   A juggler who produces illusions by the use of elaborate
   machinery. [Obs.]

         Divers appearances Such as these subtle tregetours
         play.                                    --Chaucer.