Fusible plug

A fusible plug is like a special kind of plug that is used in big machines that make a lot of heat. It's like a little piece of metal that is designed to melt when it gets really hot.

When the metal melts, it creates a little hole in the machine where the plug was. This hole is designed to let out steam or some other kind of gas so that the machine doesn't explode or get damaged from too much heat.

So, just like when you have a fever and your mommy gives you medicine to make the fever go down, the fusible plug is like medicine for the big machine. It helps keep it from getting too hot and getting sick.