Okay kiddo, frangibility is a big word that means how easy something can break or fall apart into small pieces when it is hit.
Think about your crackers at snack time. You can easily break them into little pieces with your fingers or when you bite into them, right? That means they are frangible.
On the other hand, imagine you have a strong metal toy car. Even if you drop it on the ground, it won't break into small pieces. That's because it's not frangible, it's tough!
Frangibility is important because it helps keep things safe. For example, if an airplane crashes, we want parts of the plane to break apart into small pieces so that they don't hurt people on the ground. That's why some parts of planes are made to be frangible.
So frangibility is just a fancy way of saying how easy something can break into small pieces, and it helps us stay safe. Cool, right?