Technically, a zombie is an animated corpse resurrected by mystical means. In modern times, we’ve expanded the term to mean any undead being (though not vampires) regardless of the means of reanimation.
In traditional Vodou (or voodoo), a dead person can be revived by a sorcerer. The sorcerer retains control of the zombie, since it has no will of its own.
Outside of mystical means, there are other possible causes of the zombie myth.
There are two powders, that when introduced into the blood stream (usually via a wound), can produce zombie-like behavior in a living person.
The first, coup de poudre, includes tetrodotoxin, a frequently fatal neurotoin found in the flesh of the pufferfish. The second powder consists of dissociative drugs that would produce a psychotic state.
Taken together, the first drug would produce an initial state of deathlike suspended animation. The second would then lead to psychotic behavior after “re-awakening”.
Modern fiction and movies often portray zombies as rising from a virus or contagion that reanimates them. Hunger for flesh is usually the driving force for the modern zombie, though they also have no will of their own beyond that.
Regardless of how they are reanimated, zombies are a frightening myth of an unstoppable creature that can’t be reasoned with. Mindless and dead, they exist only to destroy.
For my story, humans in space would encounter an alien culture made of “zombies”. The aliens live their “first life” alive as we understand life, and after they die, they are reanimated and begin their “second life”. With humans considering the dead to be evil, the human explorers have much adjusting to do to understand this new culture.
Would you ever write a story about zombies?