When you go to sleep at night, you probably have a favorite stuffed animal or toy that you like to cuddle with. A hossu is kind of like that for very special people called monks.
Monks are people who spend a lot of time practicing their religion and trying to be good and kind. As part of their religious practices, they have a special kind of tool called a hossu. It's a long stick with strings attached to it, and at the end of the strings, there are soft and fluffy bits of cloth or feathers.
When the monk is praying or meditating, they can use the hossu to help them focus and be calm. They'll wave it back and forth, making the fluffy bits swoosh through the air and create a soft, soothing rustling sound. It's like having a little friend to help them feel peaceful and happy.
So just like you have your favorite toy to help you feel relaxed and cozy as you drift off to sleep, a hossu is a special tool that helps monks feel calm and centered as they practice their religion and try to be good and kind people.