What's does a hard and painful lump on the wrist mean?

Ganglion Cyst: A ganglion cyst is a tumor or swelling on top of a joint or the covering of a tendon (tissue that connects muscle to bone). It looks like a sac of liquid (cyst). Inside the cyst is a thick, sticky, clear, colorless, jellylike material. Depending on the size, cysts may feel firm or spongy.

Mass: It may or may not be anything to worry about. It could be a lipoma or ganglion. There are serious masses too. Have a hand surgeon take a look.

Mass: There a number of different thing this could be, but the most common mass in the hand is a ganglion cyst. Have a hand surgeon take a look at it.