I have a large bump on the rt side of my skull 1/2in above my ear. Its been there for 6 mo. And hasn't grown or shrunk. No other symptoms. What is it?

Lymph node. This is most likely a lymph node. There is a batch of them around the ear. They enlarge with response to inflammation/infection and can remain elarged for months. Let your doctor check it out at your next physical so they can keep an eye on it.