diel·​drin ˈdēl-drən How to pronounce dieldrin (audio)
: a white crystalline persistent toxic chlorinated compound C12H8Cl6O used especially formerly as an insecticide

Example Sentences

Recent Examples on the Web As a result of a lawsuit filed by the fund in Michigan, nearly every city stopped using DDT, and an application of another pesticide, dieldrin, in Western Michigan, to fight Japanese beetles, was delayed for a year. Richard Sandomir, New York Times, 18 Feb. 2022 Many are also insusceptible to later pesticides like dieldrin, malathion and deltamethrin. Charles C. Mann, WSJ, 26 Apr. 2018 The environmental assessment found the presence of toxaphene and dieldrin, decades-old insecticides that are now banned and have been shown to cause cancer in mice. Skyler Swisher, Sun-Sentinel.com, 10 Apr. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'dieldrin.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History


Diels-Alder reaction (an addition reaction forming a 6-membered ring), after Otto Diels & Kurt Alder

First Known Use

circa 1949, in the meaning defined above

Time Traveler
The first known use of dieldrin was circa 1949

Dictionary Entries Near dieldrin

Cite this Entry

“Dieldrin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/dieldrin. Accessed 26 Nov. 2022.

Medical Definition



diel·​drin ˈdē(ə)l-drən How to pronounce dieldrin (audio)
: a white crystalline persistent chlorinated hydrocarbon insecticide C12H8Cl6O
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