The Collaborative International Dictionary of English v.0.48:

Trudge \Trudge\, v. i. [imp. & p. p. Trudged; p. pr. & vb. n.
   Trudging.] [Perhaps of Scand. origin, and originally
   meaning, to walk on snowshoes; cf. dial. Sw. truga, trudja, a
   snowshoe, Norw. truga, Icel. [thorn]r[=u]ga.]
   To walk or march with labor; to jog along; to move wearily.
   [1913 Webster]

         And trudged to Rome upon my naked feet.  --Dryden.
   [1913 Webster]

WordNet (r) 3.0 (2006):

trudge
    n 1: a long difficult walk
    v 1: walk heavily and firmly, as when weary, or through mud;
         "Mules plodded in a circle around a grindstone" [syn:
         slog, footslog, plod, trudge, pad, tramp]