Courtesan. A courtesan, in modern usage, is a euphemism meaning an escort, mistress or a prostitute, for whom the art of dignified etiquette is the means of attracting wealthy, powerful, or influential clients.
   The term originally meant a courtier, a person who attends the court of a monarch or other powerful person. In feudal society, the court was the centre of government as well as the residence of the monarch, and social and political life were often completely mixed together.
   Prior to the Renaissance, courtesans served to convey information to visiting dignitaries, when servants could not be trusted. In Renaissance Europe, courtiers played an extremely important role in upper-class society.
   As it was customary during this time for royal couples to lead separate lives, commonly marrying simply to preserve bloodlines and to secure political alliances, men and women would often seek gratification and companionship from people living at court. In fact, the verb to court originally meant to be or reside at court, and later came to mean to behave as a courtier and then courtship, or to pay amorous attention to somebody.
   The most intimate companion of a ruler was called the favourite. In Renaissance usage, the Italian word cortigiana, feminine of cortigiano came to refer to a person who attends the court, and then to a well-educated and independent woman, eventually a trained artist or art
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