This article examines French and Russian terminological units that describe the current systems of gestural communication. The author studied scientific articles, dictionaries, non-fiction, and law texts to conduct a definitional and context analysis of lexical units that form a lexical-semantic continuum between the expression of the concept of oral language and the concept of sign language in the corresponding metalanguages. The study revealed linguistic and extralinguistic factors that determined ethical problems associated with the incorrect translation of certain terms from French into Russian. The fundamental distinction between the concepts of language and speech made it possible to systematize all the units identified as part of this terminological field in both Russian and French. The systems were presented as tables that illustrated the boundaries of the concepts. A comparative analysis of the two systems indicated the main morphological and semantic differences in the terms. The research resulted in a system of equivalence between French and Russian terms, i.e., a scientifically based nomenclature that can be used by linguists and translators when working on Russian and French texts in the field of communication of deaf and hard of hearing people.