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para-dichlorobenzene

American  
[par-uh-dahy-klawr-uh-ben-zeen, -ben-zeen, -klohr-] / ˌpær ə daɪˌklɔr əˈbɛn zin, -bɛnˈzin, -ˌkloʊr- /
Or paradichlorobenzene

noun

Chemistry.
  1. a white, crystalline, volatile, water-insoluble solid, C 6 H 4 Cl 2 , of the benzene series, having a penetrating odor: used chiefly as a moth repellent.


Etymology

Origin of para-dichlorobenzene

First recorded in 1875–80; para- 1 + di- 1 + chloro- 2 + benzene