The semantic evolution of words in the context of time represents a cultural, political, social, and economical process. The advantage of reviewing some influential words in human history is to reveal the relative developments and unfold many hidden historical facts from among the documents and events. The word “Deylam” has had a noticeable transformation and development in both linguistic and cultural aspects. Some linguistic theories contribute to define “Deylam” within its several applications. “Deylam”, initially the name of a tribe, has had more than twenty other meanings in history. Those meanings, regarding the name of the places they inhabit, were formed in limitation, development and transformation.