That's a good start, but it's not quite the complete definition of refraction. Here's a more accurate explanation:

Refraction is the bending of a wave (like light or sound) as it passes from one medium to another at an angle.

Here's why your definition needs some tweaking:

* Not just Earth's mediums: Refraction occurs whenever a wave passes from one medium to another, regardless of whether those mediums are on Earth or not. For example, light refracts as it passes from air to water or from glass to air.

* The angle is key: The bending of the wave is a result of the change in speed of the wave as it transitions between the mediums. This change in speed causes the direction of the wave to change, resulting in the bending.

Think of it like this: Imagine a car driving across a field and then hitting a road. The car will change speed as it goes from the rough field to the smooth road, and this change in speed will cause the car to change direction slightly. Refraction works in a similar way with waves.