Cuff is a slur used to describe Blacks in a derogatory way. Heard used by white southern Georgia farmers to describe blacks. The origin is that blacks are always being arrested and being hand"cuffed" by the police.
The word Cuff 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 Cuff, it is best to err on the side of caution and avoid using it in any situation.