Noun
a toxic war gas with sulfide based compounds that raises blisters and attacks the eyes and lungs; there is no known antidote
Source: WordNetSulfur mustard agents (class) The complete list of effective sulfur mustard agents commonly stockpiled is as follows: History Development Mustard agent was possibly developed as early as 1822 by César-Mansuète Despretz (1798–1863). Source: Internet
Sulfur mustard is a viscous liquid at normal temperatures. Source: Internet