The short and sweet meaning that applies here is, "A well-mannered and considerate man with high standards of proper behavior."
I couldn't have said it better.
But I have a feeling this going to turn into something that is very difficult to explain. I had a psychology teacher who gave us an assignment to describe the physical differences between a dog and a cat to a person who has no knowledge of either. Well I thought, OK sounds easy enough. Cats have whiskers, sharp teeth, a tail, different patterns of hair, 4 legs, claws, paws....wait so does a dog.
Summary, you just know what one is and you know what one isn't.