The Collaborative International Dictionary of English v.0.48:

Fyrd \Fyrd\, Fyrdung \Fyr"dung\, n. [AS.; akin to E. fare, v.
   i.] (Old. Eng. Hist.)
   The military force of the whole nation, consisting of all men
   able to bear arms.
   [1913 Webster]

         The national fyrd or militia.            --J. R. Green.
   [1913 Webster]