made up of two words: "Fi" and "tness".
But it's funny. What is fitness? Is it lifting weights? Is it running, bicycling, swimming, roller-skating? Is it eating healthy? Is it eating what you want and then sweating it out later at the gym?
The point is this: Fitness isn't just one specific thing. It's many things and has just as many evolutions in meaning to the people that pursue it. I would venture a guess that a good majority of the people have at least one aspect of their life that they would like to be more "fit" in doing. Find what works for you. Get a trainer. Join a running club. Cycle to fight breast cancer.
"Do what moves you...literally." That's a Chris-ism regarding fitness (tm).