This present paper looks at migration and borrowings concerning the particular scientific terms of lin-guistics terminology. From an etymological analysis of two terms in French, morphème and phonème, we will observe how they were introduced into the French lexicon. We will examine the history of these French vocables in order to consider how kinds of borrowings they are. The etymological study will be completed by a sociolinguistic approach so as to explain that internationalisms must be considered within a linguistic system. The borrowing is a choice and we’ll show that scientific terms lose their arbitrary nature in this choice.