defoliant

noun

de·​fo·​li·​ant (ˌ)dē-ˈfō-lē-ənt How to pronounce defoliant (audio)
: a chemical spray or dust applied to plants in order to cause the leaves to drop off prematurely

Examples of defoliant in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
It was used as a defoliant in Vietnam. — Angus Chen, STAT, 27 Mar. 2026 It was believed this was a result of exposure to Agent Orange, the chemical defoliant used in the Vietnamese jungles. — Chicago Tribune, 26 May 2025 American planes roaring overhead, releasing bombs, rockets and defoliants like Agent Orange, became part of their everyday existence. — Saqib Rahim, NBC News, 17 Apr. 2023 This protection also covers exposures to chromium, chemical defoliants, Agent Orange, and asbestos. — K.h. Koehler, Ascend Agency, 8 May 2026 See All Example Sentences for defoliant

Word History

First Known Use

1943, in the meaning defined above

Time Traveler
The first known use of defoliant was in 1943

Browse Nearby Words

defog
defoliant
defoliate
See all Nearby Words

Cite this Entry

“Defoliant.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/defoliant. Accessed 7 Jul. 2026.

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Kids Definition

defoliant

noun
de·​fo·​li·​ant (ˈ)dē-ˈfō-lē-ənt How to pronounce defoliant (audio)
: a chemical that is applied to plants and causes their leaves to drop off

More from Merriam-Webster on defoliant

Nglish: Translation of defoliant for Spanish Speakers

Britannica.com: Encyclopedia article about defoliant

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