vagrant
     adj : continually changing especially as from one abode or
           occupation to another; "a drifting double-dealer"; "the
           floating population"; "vagrant hippies of the sixties"
           [syn: {aimless}, {drifting}, {floating}, {vagabond}]
     n : a wanderer who has no established residence or visible means
         of support [syn: {drifter}, {floater}, {vagabond}]
Source: WordNet® 2.0