Friedrich Adolf Paneth FRS (31 August 1887 – 17 September 1958) was an Austrian-born British chemist. Fleeing the Nazis, he escaped to Britain. He became a naturalized British citizen in 1939. After the war, Paneth returned to Germany to become director of the Max Planck Institute for Chemistry in 1953. He was considered the greatest authority of his time on volatile hydrides; he also made important contributions to the study of the stratosphere. He was an enthusiastic amateur photographer (using the autochrome method) all his life.
Paneth's conception of ″chemical element″ functions as the official definition adopted by the IUPAC.