Someone who is of combined heritage: hispanic and black. It's a portmanteau of the words "Spanish" and "Black" to form "Splack". Ironically, half the time they seem like neither. They may or may not use stereotypes of both cultures and combine them to form an Ultimate Minority. The term is meant in a humorous and non-racist way.
"Yeah, I'm half Spanish, half Haitian. Splack. It's easier to remember."
"By being Splack, I am a serious threat to the chicken population."