Uncertain. Perhaps derives from the Hungarian word bocskor, meaning a certain sole-less footwear used by Balkanic shepherds, in Romanian called opincă. Often considered to have originally meant "man without a country" in Hungarian, but this is probably not true. Hungarians on the other hand believe the word may have instead come from Romanian or Slavic. Another less likely theory suggests the verb boscorodi ("to grumble, murmur").
The word could also originate from Turkic bozkır meaning steppe.
The word could also originate from Posle Gora an old Slavic name of Transylvania (Trans = beyond,over,trough; Sylva = forest) heard by Romanians . The word "gora" is mean forest in Slavic languages, the "posle" is mean after,beyond. "Posle gora"- after the worse, which is a synonym for: after/beyond a hard-deep forest. The evolution of the word: Posle Gora (trans-silva) -> Posgora -> Bosgora -> Bosgor -> Bozgor. So, the word bozgor is likely mean "transilvanian" instead of "man without country".