eager
Feeling very excited and unable to wait for something.
To be eager means to feel excited and impatient about something you really want to do or have happen. When you're eager for summer vacation, you can barely sit still during the last week of school. When you're eager to try a new video game, you keep asking when you can play it.
Eagerness shows in how you act: an eager student raises their hand quickly, sits forward in their seat, and pays close attention because they genuinely want to learn. An eager player arrives early to practice and volunteers for drills. You can hear eagerness in someone's voice when they ask rapid questions about something that interests them.
The word has a positive energy to it. Being eager isn't the same as being demanding or whiny. Someone who's eager to help wants to pitch in, while someone who's eager to learn seeks out new information and skills. Teachers love eager students because their enthusiasm makes the whole class more interesting.
You might be eager for Friday, eager to see a friend, or eager to show your parents something you made. That feeling of happy anticipation, where you can hardly wait for something good to happen, is eagerness.