0 the brand name for a small soft ball that is often kicked in the air in games -- 沙包球,毽球,足沙包(Hacky Sack 本来是这种球的一个牌名称,后用来泛指这种球或体育活动)
The teacher tried giving boys hacky sacks to help them release energy and stimulate thinking.
Combining the skills of volleyball, football, gymnastics and hacky sack might seem difficult to most of us.