How about background?
A zombie (Haitian French: zombi, Haitian Creole: zonbi) is a mythological undead corporeal revenant created through the reanimation of a corpse. Zombies are most commonly found in horror and fantasy genre works. The term comes from Haitian folklore, in which a zombie is a dead body reanimated through various methods, most commonly magic like voodoo. Modern media depictions of the reanimation of the dead often do not involve magic but rather science fictional methods such as carriers, radiation, mental diseases, vectors, pathogens, parasites, scientific accidents, etc