Six is a slur used to describe Blacks in a derogatory way. In the times of political correctness this is a good way to say Nigger without getting jumped. I belive it has to do with 6 letters in the word nigger. To use in a sentence; "Hey, look at that 6 over there."
The word Six 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 Six, it is best to err on the side of caution and avoid using it in any situation.