White-wash is a slur used to describe Mixed races in a derogatory way. To be White-washed is to lose all culture after coming to the United States; also "bleached."
The word White-wash is a racial slur that has been used historically to degrade and dehumanize mixed races. The word is still used by some people for this purpose, and it is seen as offensive and hurtful to mixed races. If you are unsure about whether or not it is appropriate to use the word White-wash, it is best to err on the side of caution and avoid using it in any situation.