What does “Zako” mean?

Definition
The Japanese term “Zako” (雑魚) originally comes from fishing terminology, referring to small, low-value fish that are too insignificant to sell individually. Because of that origin, the word naturally carries the nuance of being trivial, weak, or worthless.
Over time, zako evolved beyond its literal meaning and became a colloquial term in everyday and subcultural contexts, used to describe someone who is weak, unimpressive, or lacking presence. In video games, for instance, it’s often used to refer to minor enemies that are so weak they can be defeated effortlessly — the classic example being the Slime from Dragon Quest.
In recent years, zako has taken on an additional layer of meaning. It’s sometimes used by women in a teasing or mock-insulting way toward men — what you might call an “affectionate insult” or “rewarding kind of teasing.” Among female VTubers, it has even become part of fan culture: viewers sometimes donate money just to be called “zako” by their favorite streamer, turning the word into a unique form of audience interaction.
Example
You’re such a useless zako…
Thank you! That’s a compliment


