To hold tightly or grasp something firmly. She had to hang on to the railing to avoid slipping on the icy steps.
To wait for a short period of time. Hang on a minute, I'll be right back with your order.
To persist or continue despite difficulties. He decided to hang on and finish the project, even though it was challenging.
To listen carefully or pay close attention. Hang on to every word the speaker says, as it might be on the test.