I have developed a large very hard lump on my outer right thigh, it is big and has an indent underneath it, it does not hurt but looks odd ?

Needs evaluation: I am concerned about this description. I recommend an evaluation by your primary care physician or a surgeon to determine if you need a biopsy, or should just have it removed. There are types of cancer called sarcoma which can grow like this.

Needs evaluation: While this could be benign, a couple of things you said about the lump made me concerned: it is large and it is hard. An experienced surgeon who deals with soft tissue tumors/growths such as a surgical oncologist or orthopedic oncologist will be able to distinguish a benign from a rare cancerous condition called sarcoma. This may require MRI or ct scan imaging, a biopsy, or both.