International audience Once confined to the field of scientific discourse, the environmental question has now become part of everyday discourse. Because of that, the meaning of scientific terms went through some semantic changes. As an example of this kind, this paper focuses on the uses of the loan-word "tsunami" in French written press, before and after the tsunami of december 2004. Its denotation was inclined to erode down to two main semantic features : a generic seme of "wave" and a negative axiological feature. In addition to this, the word "tsunami" developed a contextual meaning - which can be called an "anxiety generating factor" - both because of its extraneous linguistic origin, and because of its scientific grounding itself.