The Collaborative International Dictionary of English v.0.48:

bushed \bushed\ (b[.u]sht), pred. adj.
   very tired from exertion.

   Syn: all in(predicate), beat(predicate), dead(predicate),
        dead tired(predicate), knocked out(predicate).
        [WordNet 1.5]

The Collaborative International Dictionary of English v.0.48:

Bush \Bush\, v. t. [imp. & p. p. Bushed (b[.u]sht); p. pr. &
   vb. n. Bushing.]
   1. To set bushes for; to support with bushes; as, to bush
      peas.
      [1913 Webster]

   2. To use a bush harrow on (land), for covering seeds sown;
      to harrow with a bush; as, to bush a piece of land; to
      bush seeds into the ground.
      [1913 Webster]

WordNet (r) 3.0 (2006):

bushed
    adj 1: very tired; "was all in at the end of the day"; "so beat
           I could flop down and go to sleep anywhere"; "bushed
           after all that exercise"; "I'm dead after that long trip"
           [syn: all in(p), beat(p), bushed(p), dead(p)]