Weltschmerz is a German word that means "world pain". It is when someone feels sad or disappointed because of the way the world or society is. You might feel weltschmerz if you see people not taking care of the planet and feel like there is nothing you can do or if you see something unfair happening in the world and feel like you can't do anything to help. It is like feeling heavy-hearted or helpless because of the problems the world has.