Genealogy of the term advent of Mahdi - Allaihe Salam (PBUH) in Islamic sources

Mahdism, as the highest teachings on the great messianic culture of Ahlul-Bayt (alaihe salam), has a few terms and expressions that have gained some special meanings fit for its learned condition. As vocabulary study of the content of any knowledge always draws benefit, it is of special importance and great religious thinkers have always made efforts to explain these terms and expressions used in religious texts. A scientific study of these terms can aid a more comprehensive explanation of it.
In this study, we have attempted to use the words from the infallible Imams on the basis of their narrative to answer several questions among Mahdavi terms, e.g. we aim to find out the definition of rise, appearance and exit and understand their meanings. Moreover, to what extent the literal meaning is intended? And whether the emergence coincides or is the same as uprising? And what other words are used to describe this big event? Undoubtedly, the new findings in response to these questions are the merits of this study which can be found in few papers written prior to this.