When you romp, you move around in a loud, rough, playful, silly way. Or, when you romp to a place, you move there in a fast, easy, silly way.
Romping is usually something that kids or animals do. If you look silly and you're making a mess, but you don't care because you're having fun and burning off your extra energy, you're probably romping.
Here's a goat romping around with a ball. We call this "romping" because it's playful behavior that's noisy and full of energy.
Romping is usually a little rough! It's NOT romping if you and your friends are talking normally as you build a sandcastle together. But it IS romping if you're pushing each other, falling over in the sand, and shouting loudly at each other. You're not mad, you're just wild: that's romping.