Aptronym is a name that means what it says
..or at least close.
What an aptronym is really all about is a much like a person's name is a synonym for what they do or are all about. The best way to show how this works is to provide some examples of names that are aptronyms. They are just names that are well-suited to the person as we may know them. In short, it is an appropriate name.
Any person named Ball who plays a professional sport with a ball involved in the game is one simple example. Justin Case would be a good example of a name for the stand-in at a Broadway stage presentation. I actually worked with a credit manager who was named Mike Cash. He was a very nice person as well even though that has nothing to do with the fact that his name is an aptronym.
Some examples that you might recall through history are the following:
Thomas Crapper - an actual toilet manufacturer
Cecil & Prince Fielder - baseball players
Chuck Long - quarterback (chuck is slang for throw)
Lake and Scott Speed - race car drivers
Usain Bolt - sprinter who might be considered the fastest man on record. He holds the current records for the 100 and 200 meter dash.
Chris Moneymaker - winner of $2.5M in the 2003 World Series of Poker, an accountant no less. It is his birth name.
Martin Short - actor and comedian who just happens to be short. In today's world someone would try to call him Martin "Vertically-Challenged".
And of course my favorite would be Dr. Pokemon for a Jamaican proctologist. Perhaps that is why Usain Bolt runs so fast. "You stay away frum me u crazee mon wit dose fro-zen hans of yours!"