noun chlo·ro·thal·o·nil \ˌklȯr-ə-ˈtha-lə-ˌnil\

Definition of chlorothalonil

  1. :  an organochlorine fungicide C8Cl4N2 that protects against a wide range of fungal diseases and is used especially on agricultural crops (such as peanuts and tomatoes) And, although chlorothalonil is an excellent home garden fungicide, and oil sprays are highly effective against mites and other soft-bodied insects, the two are not compatible and cannot be combined or used within several days of each other. — H. S. Stevens, Dallas Morning News, 28 May 1999 … one of the most widely used fungicides on crops in the United States, chlorothalonil, raises mortality rates among frog tadpoles at low concentrations. — Susan Milius, Science News, 11 Sept. 2010

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First Known Use of chlorothalonil


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a brief usually trivial fact

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