Debris flow had been called in the various ways in Japanese, such as “Yama-tsunami”, “Yama-shio”, “Oshidashi”, or “Teppou-mizu”. This paper shows how the debris flow has been called academically, administratively, linguistically, or in journalistic ways. There are differences in transitions in the expressions of debris flow between academic, administrative, linguistic or journalistic ways. For example, “Doseki-ryu” was firstly used in the textbook of the Sabo engineering in 1916, while newspapers generally began to use “Doseki-ryu” in mid-1970 s. Until mid-1970 s, they used “Yama-tsunami” or “Teppou-mizu”. These transitions were executed with regard to the historical and social backgrounds.
Here I also examined the origin of “Doseki-ryu” using literatures of France and Austria, because these countries had already done many studies about debris flow in 19^th century. Based on these investigations, it can be thought that “Doseki-ryu” was composed by combining “doseki (stones and soils)” and “ryu (flow)”. While, other terms, like “Yama -tsunami”, are metaphoric expressions, “Doseki-ryu” can be considered to be very reasonable technical term, in terms of situation of occurrence, flow materials, behaviors of flow and linguistics.