The word “zombie” is never used. The most common euphemism used to describe the living dead is “those things,” mostly by Cooper. Other characters refer to the creatures as “ghouls” and “flesh eaters”. However, the film codified many tropes about zombies that have been used in many movies since, including zombies eating human flesh and that zombies can only be killed by shooting them in the head.

Night of the Living Dead (1968), dir. George A. Romero