Jan Szczepan Otrębski[a] (8 December 1889 – 26 April 1971) was a Polish philologist, linguist, and author of 350 scientific papers in the field of Slavic and Baltic studies.
[1] He held the Chair of Baltic Philology in the Adam Mickiewicz University in Poznań and was the founder of the Lingua Posnaniensis journal.
[2] He studied at the University of Warsaw, where he met Yefemiy Karski who was the supervisor of his first thesis, "Description of Byelorussian Dialects in Vilnius Province".
When the war ended, Otrębski submitted his doctoral thesis, titled "Przyczynki do gramatyki porównawczej języków indoeuropejskich" ("Contributions to a Comparative Grammar of the Indo-European Languages"), to Professor Jan Michał Rozwadowski at Jagiellonian University, and he defended the dissertation in 1920.
[6] His three-volume work titled Gramatyka języka litewskiego (Grammar of Contemporary Lithuanian) is considered his magnum opus.