bummed

from The Collaborative International Dictionary of English v.0.48

bum \bum\, v. i. [imp. & p. p. {bummed}; p. pr. & vb. n.
   {bumming} (?).] [See {Boom}, v. i., to roar.]
   To make murmuring or humming sound. --Jamieson.
   [1913 Webster]

   {to bum around} to wander about idly or aimlessly.
      [PJC]