diphenylchloroarsine

noun

di·​phe·​nyl·​chlo·​ro·​ar·​sine -ˌklōr-ō-ˈär-ˌsēn, -ˌklȯr-, -sən 

variants also diphenylchlorarsine

-ˌklōr-ˈär-, -ˌklȯr- 

: a colorless crystalline arsenical (C₆H₅)₂AsCl used during World War I especially by the Germans for producing a toxic smoke causing sneezing and vomiting