From the Greek adjective phlogistos, burned, consumed by fire. A presumed substance of bodies devised by the last alchemists apprentice chemists of the seventeenth and eighteenth centuries to explain combustion. The 17th century German alchemist-chemist Johann Becher called it terra pinguis. At the end of the eighteenth century, Antoine Lavoisier eliminated it. It was not necessary to suppose their existence to explain the combustion of bodies. The existence of oxygen, whose name he coined in 1777, was necessary.