We are increasingly called upon to collaborate and share information. The fact remains that we must agree on the meaning of words. The first step is to define the terminology of a domain. This implies a long and difficult task for specialized domains. If it is still difficult to find consensus on the definition of natural language, experience in various communities of practice shows that this is not the same for formal conceptualization of a domain in which experts generally agree. Based on this fact, we introduced a new paradigm, that of ontoterminology. The main idea is to separate the linguistic dimension of the conceptual dimension of terminology. We present the results of this new paradigm applied to the domain of hydraulics.