1860-1943, Danish linguist with French as his principal subject and Latin and English as his minor subjects, Professor of English Language and Literature at Copenhagen University 1893-1925.
Jespersen had great influence in several linguistic fields. In 1890 he established the phonetic notation Dania, which is specially adapted for Danish and therefore used in several major Danish reference works, and he published Modersmålets fonetik (1906, The Phonetics of the Vernacula).
Jespersen's best-known works on English include A Modern English Grammar on Historical Principles, 1-7 (1909-49). In addition he used his wide knowledge of both English and general phonetics to prepare a much used textbook system for teaching English from the elementary stage.
He also played a significant role within general linguistics, for instance with the publication Language, its Nature, Development and Origin (1922) and Børnesprog (1923, Children's Language). Further evidence of Jespersen's great interest in language and immense capacity for work is his involvement in the composition of the artificial language Ido around 1907 and the development of his own artificial language Novial, presented in 1928.
Jespersen was not only an extremely talented and productive linguist, but also an excellent communicator, both in speech and writing. From 1934 until his death he lived in the honorary residence of the Royal Danish Academy of Sciences and Letters in Elsinore. Signe Holm-Larsen, Gyldendal Leksikon