The use of the term for the Iranian language family was introduced in 1836 by Christian Lassen. Robert Needham Cust used the term Irano-Aryan in 1878, and Orientalists such as George Abraham Grierson and Max Müller contrasted Irano-Aryan (Iranian) and Indo-Aryan (Indic). Some recent scholarship, primarily in German, has revived this convention.
Who first used the term Iranian language?
Christian Lassen