Bubba is a slur used to describe Blacks in a derogatory way. When referring to prison, the big guy who takes advantage of all the new prisoners is derogatorily called Bubba.
The word Bubba is a racial slur that has been used historically to degrade and dehumanize blacks. The word is still used by some people for this purpose, and it is seen as offensive and hurtful to blacks. If you are unsure about whether or not it is appropriate to use the word Bubba, it is best to err on the side of caution and avoid using it in any situation.