There's no anti-white slur thats offensive. One is purported to mean 'Dirty scum from the sea'. But its also used in a respectful way so the sentiment is lost. https://www.news24.com/news24/umlungu-the-accepted-racist-word-20130724 I think your level of offense depends on the size of the chip on your shoulder, skin thickness, and desire for victimhood.