Hey kiddo, do you know what a relation is? It's like a way of comparing two things and seeing how they relate to each other.
Now, an antisymmetric relation means that if we compare two things and one is related to the other, then the other thing cannot be related back to the first in the same way.
For example, imagine we're comparing animals based on their cuteness. If we say that a bunny is cuter than a squirrel, then we cannot say that the squirrel is cuter than the bunny. That's because the relation is antisymmetric - it goes only one way.
In the same way, if we compare numbers based on size and say that 5 is greater than 3, we can't say that 3 is greater than 5. Again, the relation only goes one way.
Does that make sense to you? It's like a one-way street - once you go down a certain road, you can't turn back and go the other way.