Television deep-dive site TV Tropes explains that the phenomenon might have to do with something called “genre blindness”.
“Genre blindness” happens when a character seems so unfamiliar with the trope a work is part of that they don’t act as an audience member, who knows about it, would.
The Walking Dead creator Robert Kirkman seems to use this trope, revealing in The Cutting Room Floor with Robert Kirkman that showrunner Frank Darabont “didn’t want to use the term, feeling like it wouldn’t exist in this world if zombie fiction didn’t exist in this world”.
“Really, for this story to work, you can’t just have people saying, ’You shoot them in the head, y’know… just like the zombies from the Romero movies!” he added.
“So you have to assume this is a universe where George A. Romero didn’t create the modern zombie. So, we coined the term ‘walkers’ for the show.”
This is especially common in movies and TV shows that want to appear “real”.
While it would be realistic for you or me to scream “Zombies!” at the sight of an undead human craving some cerebellum, that “realism” might lose the story some suspense.
If the character has no idea what a “Z word” is, though, we can still just about suspend our disbelief as a definitely-not-zombie makes steak medull-ians of the cast’s brains.
No. There’s also a TV and movie (and book, and stage…) trope called lampshade hanging which explains some non-zombs.
It’s the writer’s way of drawing attention to the fact that they know what’s happening would never occur in real life.
It can also address the very obvious use of a trope (a good example is Shaun Of The Dead’s “Z word” comment).
Not calling zombies “zombies” can also be a way to show the audience your monsters aren’t like other grey matter feeders.
We all think we know what a zombie, vampire, or witch is, so we might miss the nuances the writer has added to their undead when we hear the name, TV Tropes says.
Perhaps changing the name can lead us to look at the creations with more open braiiiiiiinssssssssss…
