This article aims to present the collective research that has been made in the framework of the research seminar "Vocabulary of the Virtual" organized by IRCAV (Institute of Research on Cinema and Audiovisual Studies), Sorbonne Nouvelle and the "Spatial Media" group, EnsadLab. The main topic is to clarify the notions that refer to the concept of the "Virtual" in order to define it through an interdisciplinary approach according to different fields of science (aesthetics, philosophy, film theory, sound theory, ergonomics, design, engineering, cognitive sciences, etc.). This article presents many different conceptual tools such as cartography, mental maps, notional diagrams with several dimensions, etc., that have been conceived over the last three years, to show how the reflection on the concept of the Virtual was first established and constructed, and how it has been developed. The notion of symbiosis seems to be defined as a structuring notion of the concept of the Virtual across the process of anchoring the levels of virtuality inside technological devices and concrete sites, as well as inside the physical body of the VR users. The user's body serves as a catalyst for the concept of the Virtual which then becomes organic.