Born July 16, 1860, in Randers; died Apr. 30, 1943, in Copenhagen. Danish linguist.

Jespersen became an English-language professor at the University of Copenhagen in 1893. His textbook on English (1895), published in 19 editions, was based on lively everyday speech. In The Philosophy of Grammar (1924), Jespersen revealed his concept of grammar as an active and developing entity. He introduced the “theory of progress” in language, maintaining that all linguistic changes serve to simplify communication and are therefore progressive. Jespersen devised the international artificial language Novial. His works have influenced 20th-century linguistics.