The term 'Roman Greeting' refers to two common greetings used in the Roman Empire. The first is 'CIAO, ' which is an informal greeting that is still used today in many parts of the world. It is derived from the Venetian dialect and is believed to have originated in the 14th century. The second greeting is 'AVE, ' which is a formal greeting that was used in Latin and is still used in some religious contexts today. Both of these greetings were commonly used in the Roman Empire and are still used today.