pogo
To jump straight up and down again and again.
A pogo stick is a spring-loaded toy that lets you bounce up and down while standing on it. You grip handles at the top, place your feet on pegs near the bottom, and push down to compress a powerful spring. When the spring releases, it launches you into the air. With practice, you can bounce continuously, hopping around your driveway or sidewalk.
Pogo sticks were invented in the 1920s and became a huge craze. Kids would see how many bounces they could do in a row or how far they could travel without falling off. Modern pogo sticks can launch riders several feet high, and some athletes perform amazing tricks like backflips.
The word pogo has also become a verb meaning to jump up and down repeatedly in one spot, especially at concerts where people pogo to energetic music. When you imagine someone bouncing straight up and down with both feet together, that's pogoing.
Getting good at a pogo stick takes persistence. You'll probably fall off dozens of times before you can bounce smoothly. But once you master the rhythm of pushing down and letting the spring do its work, you'll understand why kids have been hopping around on these things for over a century.