János Sajnovics

János Sajnovics de Tordas et Káloz (Tordas, 12 May 1733 – Pest, 4 May 1785) was a Hungarian linguist and Jesuit. He is best known for his pioneering work in comparative linguistics, particularly his systematic demonstratation of the relationship between Sami languages and Hungarian.

Sajnovics was born in Tordas. He was a pupil of the astronomer and mathematician Maximilian Hell. When Hell planned an expedition to observe the transit of Venus in Vardø, northern Norway of June 1769, he took Sajnovics with him. Hell had heard that the Hungarian and Lapp (Sami) languages were related and thought that Sajnovics, as a native Hungarian speaker, would be able to investigate the connection.

Sajnovics published the results of his research in his Demonstratio idioma Hungarorum et Lapporum idem esse (1770), which was a breakthrough in the study of Uralic languages. His ideas were further developed by Samuel Gyarmathi and Ágoston Gellért.

He died, age 51, in Pest, Hungary.