Definitions

1. noun

a ball used in the martial art of Kyokushin karate, typically made of sand or a similar heavy material, used for training and improving punching technique

“The instructor had the students practice their punches on the heavy dragonball.”

2. noun

a fictional energy sphere used in the popular manga and anime series Dragon Ball, often used to store and release large amounts of energy

“The powerful ki was stored within the dragonball, waiting to be unleashed.”