Main Entry: lew·is·ite

Pronunciation: \ˈlü-ə-ˌsīt\

Function: noun

: a colorless or brown vesicant liquid C₂H₂AsCl₃ developed as a poison gas for war use

Lewis, Winford Lee (1878–1943), American chemist. As an officer in the United States Army Chemical Warfare Service during World War I, Lewis developed the poisonous gas lewisite in 1918. Later in life he did research for the Institute of American Meat Packers.