To stun means to shock someone so much that they can't react normally for a moment. When you're stunned, you're so surprised, amazed, or overwhelmed that you freeze up, unable to speak or think clearly.

A sudden loud noise can stun you, leaving you standing still with your heart pounding. Really good news can stun you too: imagine learning you won first place in a competition you entered on a whim. You might just stand there, mouth open, unable to process what happened. Bad news works the same way. When your brain gets information it wasn't expecting, it needs a moment to catch up.

The word also has a physical meaning. In video games, some weapons or abilities can stun opponents, making them unable to move for a few seconds.

Stunning has become a common way to describe something so beautiful or impressive it stops you in your tracks. A stunning sunset, a stunning performance, or a stunning discovery: they all grab your attention completely. When something is stunning, it has the power to make you pause and really notice it.