In the Islamic world of the early Middle Ages, the word had a loose meaning. The meaning was variable, and people gave many tribes and nomadic peoples the word Kurd. Peoples living in the mountains between Anatolia and the Iranian plateau often had the name "Kurd". In the Persian language and the Arabic language, writers during the 10th century gave the name to different ethnic groups. Some scholars make an argument that the meaning of the name was not an ethnonym at that time, because many different groups of nomads and pastoralists had the name "Kurds" during the Middle Ages. However, other scholars make the argument that the name was not the name of lifestyle or economic system (like nomadism or pastoralism) but the name of a population. This population shared a common character in linguistics, shared an area to live in, and shared a mythology. Whether the people and groups who had the name "Kurds" thought that they were a common community before the 12th century is unknown.