Boing is the sound of something bouncing or springing back, like a basketball hitting the floor or a pogo stick hitting the pavement. It's a word that sounds like what it describes: that elastic, energetic noise when something compressed suddenly releases and bounces.

You'll hear boing when someone jumps on a trampoline, when a spring pops out of an old toy, or when a cartoon character bounces off a diving board. The word captures both the sound and the feeling of springy motion. If you drop a rubber ball from a high place, it might go boing, boing, boing as it bounces several times before rolling away.

The word works as both a noun (the sound itself) and a verb. When your little brother bounces on the couch, he's boinging up and down. When writers want to describe bouncy, energetic movement, they often use boing because it instantly creates that picture in your mind. It's one of those wonderful words that does double duty: it tells you what something sounds like and what it's doing at the same time.