mal·​a·​thi·​on | \ ˌma-lə-ˈthī-ən , -ˌän\

Definition of malathion

: an organophosphate broad-spectrum insecticide C10H19O6PS2 that is considerably less toxic to mammals than parathion

Examples of malathion in a Sentence

Recent Examples on the Web

By 1966, some of the critters had also evolved resistance to then-popular pesticides such as malathion, diazinon and fenthion. Rob Dunn, Discover Magazine, "Our Attempts to Eradicate Insects are Just Making them Resistant to Pesticides," 16 Nov. 2018 Many are also insusceptible to later pesticides like dieldrin, malathion and deltamethrin. Charles C. Mann, WSJ, "‘Silent Spring & Other Writings’ Review: The Right and Wrong of Rachel Carson," 26 Apr. 2018 According to the CDC, the mosquitoes carrying the disease in Puerto Rico became resistant to the first-choice pesticide permethrin and also to malathion. Joe Raedle, National Geographic, "Zika's Accidental Ally: Miami's Luxury High-Rises," 26 Aug. 2016 Sold as Dibrom, naled is an organophosphate, a category of chemicals that also includes malathion; both are widely used to control mosquitoes. Donald G. Mcneil Jr., New York Times, "with the headline: A Mosquito Killer, Unwelcome to Many.," 17 Sep. 2016

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

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First Known Use of malathion

1953, in the meaning defined above

History and Etymology for malathion

from Malathion, a trademark

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Dictionary Entries near malathion


malar point






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The first known use of malathion was in 1953

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mal·​a·​thi·​on | \ ˌmal-ə-ˈthī-ən, -ˌän \

Medical Definition of malathion

: a thiophosphate insecticide C10H19O6PS2 with a lower mammalian toxicity than parathion

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to express emotion in a dramatic way

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