vagrant

Short definition from Wiktionary

Noun

1. 1
   A person who wanders from place to place; a nomad, a wanderer.
2. 2
   A person without settled employment or habitation who usually supports himself or herself by begging or some dishonest means; a tramp, a vagabond.
3. 3
   Vagrans egista, a widely distributed Asian butterfly of the family Nymphalidae.
4. 4
   An animal, typically a bird, found outside its species' usual range.

Adjective

1. 1
   Wandering from place to place, particularly when without any settled employment or habitation.
2. 2
   Of or pertaining to a vagabond or vagrant, or a person fond of wandering.
3. 3
   Moving without a certain direction; roving, wandering; also, erratic, unsettled.