It is known that the Ottoman provincial organization was formed from the smallest unit to the largest, in the form of village, county, town, sanjak and states (province / governorship). In the organisation and unity of these settlements, the villages constituted the counties, the counties constituted the towns, the towns constituted the sanjaks and the sanjaks constituted the states (provinces / governorship). The administrative structure of the 624-year-old Ottoman Empire changed from time to time according to internal and external circumstances. It can be seen that the term "Vilayet" used to express different administrative units in the following three periods: 1. The Period Of The Governorship System - Between 1326 and 1591; 2. The Period Of The State System - Between 1591 and 1864; 3. The Period Of The Provincial System – Between 1864 and 1922. As it becomes clear, the term “vilayet” was interpreted as "township", "county", "town", "sanjak", “castel”, "city", "country", “fatherland”, “state”, and “province” during the 624-year long period. In this study, for the first time, we have attempted to evaluate the use of the term "vilayet" in different meanings as regard three periods.
Key Words: Governorship, Province, State, Sanjak, County