Pre-Christian Greek world in its historic-religious domain records two categories of cults. There were established official and secret cults for worshipping the ancient deities. In this paper the studying field is secret, mystery cult denoted by the term ὄργια. In sixteen indicative paragraphs taken from the relevant texts of Greek authors, the last two belonging to Christian writers, the usage of the term is analyzed from the philological and historical-semasiological point of view. The term denotes par excellence the cult, addressed to concrete deity, although it can denote concrete sacrifice, sacred objects, utensils, as well as feasts and celebrations. This paper will show that the term ὄργια, although exceptionally, could denote the Christian cult too, as paragraphs of Christian authors point out. So, only when the term is used in non-cult context, it gets the negative connotation (orgies).