A barbarian is a person or tribe of people that is perceived to be primitive, savage, and warlike. A "barbarian" may also be an individual reference to an aggressive, brutal, cruel, and insensitive person, particularly one who is also dim-witted, while cultures, customs and practices adopted by peoples and countries perceived to be primitive may be referred to as "barbaric".
The term originates from the Ancient Greek: βάρβαρος (barbaros; pl. βάρβαροι barbaroi). In ancient Greece, the Greeks used the term not only for those who did not speak Greek and follow classical Greek customs, but also for Greek populations on the fringe of the Greek world with peculiar dialects. In ancient Rome, the Romans adapted and applied the term to tribal non-Romans such as the Xiongnu, Mongols, Germans, Celts, Iberians, Helvetii, Thracians, Illyrians, and Sarmatians. In the early modern period and sometimes later, the Byzantine Greeks used it for the Turks in a clearly pejorative manner.