French abstract: Il existe des termes lié s en didactique qui ne sont pas capables de caracté riser leurs efficacité s conceptuelles lorsqu’ on les emprunte dans les é chelles varié es des analyses linguistiques. La dé finition hâ tive des termes à savoir, « langue maternelle », « langue é trangè re », « langue native », « apprenant », etc., loin de toute politique linguistique ne se construisant pas autour de la notion de langue, souffre d’ une insuffisance interpré tative. Dans les contextes linguistiques et notamment l’ appropriation des langues, ces termes ne sont pas lapidaires pour suivre la totalité d’ un processus complexe. La né oté nie linguistique dé clare en toute explicite que les appellations en question souffrent d’ une insuffisance conceptuelle et d’ une opacité interpré tative n’ ayant pas un support scientifique adé quates qui ré gissent la rigueur é pisté mologique. Dans cet article nous é voquons l’ aspect terminologique de la né oté nie linguistique s’ inspirant de la psychomé canique du langage de Gustave Guillaume qui propose les termes remplaç ant à des termes non adé quats (« langue maternelle », « langue é trangè re », « langue native », « apprenant ») en didactique via la ré partition tripartite temporelle. Nous verrons que le lien cognitif entre le locuteur et les langues s’ astreint à suivre un passage opé ratif du temps guillaumien, de la puissance à l’ existence, voire, du virtuel au ré el. English abstract: Reviewing the historical aspects of linguistic theories of the previous century, we figure out that sciences of language, and precisely linguistics, are linked to a certain number of additional disciplines which allow for the emergence of new epistemologies such as neurolinguistics, psycholinguistics, sociolinguistics, etc. Undoubtedly, this fact makes it possible to focus on the nature of the findings which result from different linguistic activities as well as the cognitive procESSEs which are due to such activities. Although the overwhelming majority of linguists are more interested in the function and the use of linguistic elements, the mental component of language conditioning utterance in all its variety does not seem to be as important. This component which originates from all linguistic operations performed can be described through terms like mentalism and intuition, which offer linguistics an ontological dimension closer to the immanence of being. We must not forget that in all languages, there are abstract properties which are not visible from the outside. According to Guillaume, the universe in which we are in contact is an interior universe: the universe of the thinkable in which our representations form within us. It is obvious that the difficulty of observation, especially in the field of psycholinguistics and sociolinguistics, becomes greater when it comes to examining facts and results. These fields study the elements that are ignore at the end. The definitional inadequacies and the terminological achievements of the language sciences prompt us to question the advisability of occupying a place in the field of scientific activity that existence confers on man. The linguistic novelty devoted to the relationship between linguistics and cognitive sciences takes us away from the simple repetition of traditional names, both opaque and inadequate resulting in a naivety of meanings and interpretive opacity. Names which are observed through chronological criteria are conditioned by the passage of time. They underline the impact that the anteriority of one of the languages learnt has on the others, given the consequences that this inequality creates for the speakers. From a didactic point of view, there are two types of speakers: one who has knowledge of a language and one who is in the process of learning a language. The didactic names the former the “ native speaker” , that is to say, one who exprESSEs himself via this language since his birth. However, it turns out that it is a naive name because as long as domicile learning, or learning due to immigration are concerned, didactics are not able to offer a suitable name. How, then, do we define the term “ learning” a language when only a considerable minority of bilinguals learn the language in the classroom? What can we call the mode of learning of other “ learners” who appropriate a language in places other than language classrooms? How can we define motherhood of the mother tongue and the strangeness of the foreign language in the complex domain of monolingualism and bilingualism in linguistic reality? Didactics do not offer much help in dealing with terminologies that are intended to be more realistic. The naivety of meanings and the interpretive opacity of terms such as “ foreign language” , “ mother tongue” , “ native language” , “ learner” and many other terms prompt linguistic neoteny to lean towards new terms because maternal language is the one the child acquires through contact with the familial environment where he is raised. Therefore, the acquisition of a language is not done exclusively through contact with a biological mother. On the other hand, concerning foreign languages, it must be clarified that the possession of a language is not limited to geographic boundaries. In addition, the language acquired at an early age is not necessarily the one easily spoken in adulthood. Therefore, in this article, we try to analyse the terminological aspect of linguistic neoteny which proposes new terms to replace those in didactics, namely, “ foreign language” , “ mother tongue” , “ native language” , and “ learner” which-it seems to us-are not able to answer the questions above. To this purpose, we first analyse the guillaumian theory which continues to be the source of inspiration for linguistic neoteny. Subsequently, we schematize the approach followed by linguistic neoteny. In the end, we do not hesitate to answer the above questions with the new terminological aspects linguistic neoteny offers us.