Other forms: hoboes; hobos
Be careful when you call a vagrant or homeless person a hobo — although this is exactly what the word means, it is a somewhat offensive term.
The end of the nineteenth century brought the start of the word hobo in the Western United States. No one is certain where the word came from, although there are a couple of educated guesses. One possible origin is the English word hawbuck, which means "country bumpkin," while another is the common working man's greeting or call during the building of the railroads in the West, ho, boy!