Conceptual changes of Mihrab, emphasizingon third and fourth century AH sources

Mihrab existed before Islam. This word became one of the main components of Islamic mosques after the Islamic conquest. Structure and function changes of Mihrab during these two periods could be considered in various methods. Considering conceptual changes is one of the historical studies methods. This article aims to investigate a part of conceptual changes that reflects Mihrab’s structural and functional changes over time through collecting Islamic sources data such as dictionaries, interpretive texts, geographical and historical sources of the third and fourth centuries AH in which this word has been used many times.In this research, the method of studying time passage (historical semantics) has been used that study semantic changes in four types of narrowing, widening, degeneration and elevation. Using this method in studying semantic changes of the word Miharb in texts indicates that this word  has changed semantically from implication of the whole to implication of the component, from general meaning to specific meaning (semantic allocation),  and also from secular meaning to merely religious one (semantic promotion).