I would answer your question, but you need to rephrase it first. I don't think hunback is a word. And hump and lump have two separate meanings. If you can provide an example sentence, that would be good.
Hunchback - it is a person who has a humb on his or her back. It is normally offensive. One way of using it would be; look at that hunchback over there!
Hump - a large lump on the back of a person caused by an unusual curve in the
Hello Irnic Please tell us the context of hump and lump, and then we can tell you the meaning in context. (Are you referring to some lyrics in the latest UK record by the Black Eyed Peas?)