Anyone who has ever hurt his “funny bone” knows that there is nothing funny about this bone at all.
In fact, this “bone” is not really a bone at all; it is actually a nerve located at the back of your elbow above your bone and near the surface of your skin.
When you hit that area, you get a painful tingling feeling in your arm. This tingling travels down your arm to your ring finger and “pinky” too.
So the term “funny bone” is just an expression for something that has nothing to do with fun.