A fake smile used as a cover to hide the pain inside. It is something that certain individuals tend to use often, as a constant "mask" of their unhappiness.
1. "Look for the girl with the broken smile. Ask her if she wants to stay awhile. And she will be loved." - She Will Be Loved by Maroon 5
2. "I feel bad for her... She always seems to be wearing a broken smile, ever since her husband died. It must be hard to pretend to be happy once something like that happens."