de·​fo·​li·​ant | \ (ˌ)dē-ˈfō-lē-ənt How to pronounce defoliant (audio) \

Definition of defoliant

: a chemical spray or dust applied to plants in order to cause the leaves to drop off prematurely

Examples of defoliant in a Sentence

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Mattis visited an air base north of Ho Chi Minh City that was heavily contaminated in the late 1960s and early 1970s by American forces through storage and spillage of the chemical defoliant Agent Orange. Robert Burns, The Seattle Times, "US defense secretary sees the enduring costs of Vietnam War," 16 Oct. 2018 Mattis thanked Vietnamese officials for their cooperation in recovering missing troops and recognized the years-long U.S. efforts to clean up toxic sites in the south, where Agent Orange and other defoliants were kept. Alex Horton, Washington Post, "Vietnam War loomed over Mattis’s two days in Hanoi," 26 Jan. 2018 The haphazard method of incineration generated numerous pollutants, including carbon monoxide and dioxin—the same chemical compound found in Agent Orange, the dangerous defoliant during the Vietnam War. Perry Chiaramonte, Fox News, "Former burn pit inspector says warnings were largely ignored by Pentagon officials during Iraq War," 7 June 2018 The United States has promised to help on projects designed to remove landmines left over from the Vietnam War, address environmental concerns caused by Agent Orange defoliant pollution and account for dead troops that were missing in action. Carl Prine,, "Mattis shows that former enemy is a warming friend," 31 May 2018 In 1984, a $180 million out-of-court settlement was announced in the Agent Orange class-action suit brought by Vietnam veterans who said they'd been injured by exposure to the defoliant. azcentral, "AZ Memo: No health concerns in air around Hickman's, state reports; Bashas' wants new doughnut ideas; Phoenix is a hub for single homeowners," 7 May 2018 In 1984, a $180 million out-of-court settlement was announced in the Agent Orange class-action suit brought by Vietnam veterans who said they’d been injured by exposure to the defoliant., "This day in history," 5 May 2018 What's more, the firefighters were disproportionately likely to have a type of this disease that was also more common among veterans who were exposed to the cancer-causing chemical defoliant known as Agent Orange, the study authors noted. Karen Kaplan,, "For firefighters who worked in World Trade Center rubble, the future includes a heightened risk of cancer," 26 Apr. 2018 The ship’s mission includes technical exchanges, sports matches and visits to an orphanage and a center for victims of Agent Orange, a toxic defoliant sprayed by U.S. forces to deny cover for Communist fighters during the war. Washington Post, "Paper notes China’s ‘unhappiness’ over US Navy Vietnam visit," 7 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'defoliant.' 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 defoliant

1943, in the meaning defined above

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Time Traveler for defoliant

The first known use of defoliant was in 1943

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English Language Learners Definition of defoliant

technical : a chemical that is sprayed on plants to make their leaves fall off

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Spanish Central: Translation of defoliant

Nglish: Translation of defoliant for Spanish Speakers Encyclopedia article about defoliant

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