A shortening of bohemian
used as slang
. Can be used as a derogatory term as well.
The word Boho is liberally sprinkled through Tom Wolfe's 1968 Ken Kesey-driven opus The Electric Kool-Aid Test. The term is pretty much obsolete at this point, but it would be interesting to reintroduce it as the definition of bohemian itself has changed since 1968.