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dichlorodiethyl sulfide

American  
[dahy-klawr-oh-dahy-eth-uhl, -klohr-, -klawr-, -klohr-] / daɪˈklɔr oʊ daɪˈɛθ əl, -ˈkloʊr-, -ˌklɔr-, -ˌkloʊr- /

noun

Chemistry.
  1. mustard gas.


Etymology

Origin of dichlorodiethyl sulfide

di- 1 + chloro- 2 + di- 1 + ethyl + sulfide