Okay kiddo, imagine a giant bowl that's curved upwards instead of downwards. See how the sides of the bowl go up and get steeper as they go towards the middle? That's what a paraboloid looks like. It's a three-dimensional shape that curves up like a bowl, but in a very specific way.
A paraboloid is actually shaped like a math equation called a parabola. You don't need to worry too much about what that means, but just know that it's a fancy way of describing a curve that starts out gentle and then gets steeper and steeper. That's why a paraboloid looks like a bowl that curves up more and more towards the middle.
Paraboloids can be found all over the place. Some satellite dishes use paraboloid shape to collect signals from space. Telescopes use paraboloid mirrors to reflect and focus light. And some buildings, like the Louvre in Paris, have paraboloid-shaped roofs that make them look really cool.
So next time you see a big curved shape that looks like an upside-down bowl, you can impress your friends by telling them it's a paraboloid!