Ferdinand de Saussure, , 1857–1913, Swiss linguist. One of the founders of modern linguistics, he established the structural study of language, emphasizing the arbitrary relationship of the linguistic sign to that which it signifies. Saussure distinguished synchronic linguistics (studying language at a given moment) from diachronic linguistics (studying the changing state of a language over time); he further opposed what he named langue (the state of a language at a certain time) to parole (the speech of an individual). Saussure's most influential work is the Course in General Linguistics (1916), a compilation of notes on his lectures.