This article presents a conceptual characterization sketch of the Aljamia of the Aljamiado texts. It offers both a review of our knowledge and a new in depth interpretation from sociolinguistics. After the distinction made between Aljamia –the variety of spontaneity– and Aljamiado –an elaborated variety of distance–, it deals with the genetic process of this written variety, the process of configuration and discursive elaboration, and the practical puprose. Even though it could be considered as the discourse of the Tagarine ethnic community, Aljamiado is the production of the lettered minority of the alfaquis – a sociolect. Through its links to the domain of sacredness, it configures as a hierolect.