The Collaborative International Dictionary of English v.0.48:

Bowstring \Bow"string`\, v. t. [imp. & p. p. Bowstringedor
   Bowstrung; p. pr. & vb. n. Bowstringing.]
   To strangle with a bowstring.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Bowstringed \Bow"stringed`\, p. a.
   1. Furnished with bowstring.
      [1913 Webster]

   2. Put to death with a bowstring; strangled.
      [1913 Webster]