Okay, kiddo. Have you ever heard of a secret code or a hidden message? Well, "esoteric" is kind of like that. It means something that is really hard to understand or only known by a few people.
You know how your big sister might use big words or talk about stuff that you don't really understand? That's kind of like how "esoteric" things work. They are so difficult that only a few people really get it.
Some people like to study esoteric things, like magic or ancient religions, because it makes them feel special and smart. But it's important to remember that not everything has to be esoteric. Sometimes simple things can be really special too!