Bartholomaeus Pitiscus

Bartholomaeus Pitiscus (1561 to 1613) was a sixteenth century German trigonometrist, astronomer and theologian who coined the word trigonometry. Born to poor parents at Slone near Grunberg, now Zielona Gora in Poland, he studied theology at Zerbst and Heidelberg and, as a Calvinist, was appointed to teach the ten year old Frederick IV, Elector Palatine, later serving as court preacher to him. He won fame with his Trigonometria, printed as an appendix to a work of Abraham Scultetus, which carried the word trigonometry into English and French, and a standalone edition in 1608 added trigonometric tables. His Thesaurus mathematicus of 1613 improved the tables of Georg Joachim Rheticus, whose Opus palatinum he had helped republish in 1607. He is often credited with inventing the decimal point, and the lunar crater Pitiscus is named after him. He died in Heidelberg.