The Collaborative International Dictionary of English v.0.48:

Sinew \Sin"ew\, v. t. [imp. & p. p. Sinewed; p. pr. & vb. n.
   Sinewing.]
   To knit together, or make strong with, or as with, sinews.
   --Shak.
   [1913 Webster]

         Wretches, now stuck up for long tortures . . . might,
         if properly treated, serve to sinew the state in time
         of danger.                               --Goldsmith.
   [1913 Webster]