Source : Webster's Revised Unabridged Dictionary (1913)

Backsword \Back"sword`\, n. [2d back,n.+ sword.]
   1. A sword with one sharp edge.

   2. In England, a stick with a basket handle, used in rustic
      amusements; also, the game in which the stick is used.
      Also called singlestick. --Halliwell.

Source : WordNet®

backsword
     n 1: a stick used instead of a sword for fencing [syn: {singlestick},
           {fencing stick}]
     2: a sword with only one cutting edge