Johann Theodor Jablonski

Johann Theodor Jablonski (15 December 1654, Danzig (Gdańsk) Poland – 28 April 1731, Berlin) was a German educator and lexicographer of Czech origin, who also wrote under the pen name Pierre Rondeau.

Johann Theodor Jablonski was the oldest child of Petr Figulus (a scholar and Protestant pastor from the town Jablonné nad Orlicí in northeastern Bohemia) and Alžběta (Elizabeth), the daughter of John Amos Comenius.

Petr Figulus, who served as a secretary for his carer and subsequent father-in-law Comenius, travelled with him throughout whole Europe; finally he found asylum in Danzig.

Unlike other siblings, brothers Johann and Daniel took their surnames Jablonski (Jablonský in Czech, i.e. "man from Jablonné") from the name of father's birthplace.

In the years 1711–12, he published, under the pen name of Pierre Rondeau, a Franco-German and German-French dictionary and a grammar of the French language.