What is meant by mafioso?

The term mafioso can be used to mean members of the Mafia and also used to describe a person of prideful bearing. For example, "'What a mafioso horse!' Sicilians will exclaim when seeing a prancing stallion, well-caparisoned, with, with arched neck, dilated nostrils and fiery eyes. They obviously do not mean the horse is a member of a deadly secret society." Sicily and the Mafia, Page 254T