People's egos are so fragile that they feel more important by diminishing others by calling them names. Even though nothing has actually changed in reality, the words themselves can cause shifts in ego, and shifts in identity. In this case, you are what you say.
As for a million words: You can know a million words to describe, but never know for real. It's less about people talking "around" a subject, and more the fundamental difference between language of existance, and existance itself. Language can point the way, but it can never fully substitute for the real thing.
It's the difference between the word "tree" and an actual tree.
So is retard just a word, or do you become a retard when someone calls you one?