In the systemic approach, the system is perceived as an action or a collection of overlapping actions expressed in reference to Time, Space, and Morphology (or Energy). When the system is studied by different disciplines, the referentials differ, as well as the semantics of terms used to describe the action. In order to establish the vocabulary of a collection of actions involving several disciplines, we propose a formal method for describing each action. The linguistic-based method enables (i) transcription of the literal description of an action in a semantic network, and (ii) building of a vocabulary in a formal setting. The method is illustrated through a complex biological system, i.e. the mutualistic relationship between two vine pests, while focusing particularly on temporality. The method provides a support for implementing multidisciplinary around a complex system.