Agent Orange

American  

noun

1. a powerful herbicide and defoliant containing trace amounts of dioxin, a toxic impurity suspected of causing serious health problems, including cancer and genetic damage, in some persons exposed to it and birth defects in their offspring: used by U.S. armed forces during the Vietnam War to defoliate jungles.

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Agent Orange British  

noun

1. a highly poisonous herbicide used as a spray for defoliation and crop destruction, esp by US forces during the Vietnam War

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Agent Orange Scientific  

1. A mixture of equal amounts of two herbicides known as 2,4-D and 2,4,5-T, and trace amounts of the toxic contaminant dioxin (a byproduct of the manufacture of 2,4,5-T). It was used in the Vietnam War to defoliate areas of forest.

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Etymology

Origin of Agent Orange

First recorded in 1965–70; so called from the color of the identifying stripe on the drums in which it was stored

Example Sentences

Suspecting an environmental link, the scientists and officials considered various possible culprits, from a rare moose-borne parasite to blue-green algae blooms to Agent Orange sprayed on the province in the 1970s.

From BBC • Jan. 10, 2026

Large amounts of Agent Orange had been stored at the Da Nang airport during the war and contaminated the soil with dioxin.

From Salon • Apr. 30, 2025

Millions struggle with the aftereffects of Agent Orange and other herbicides the United States sprayed across the south, while unremediated explosives remain a mortal danger.

From Slate • Apr. 30, 2025

He died in 1994 at 45 years old from cancer likely related to Agent Orange exposure, and local advocates have worked for years to contextualize his crimes with his service-related mental illness.

From Los Angeles Times • Apr. 18, 2025

He had been ordered out many times on “search and destroy” missions after planes had sprayed the herbicide Agent Orange to kill any vegetation in their path.

From "Boots on the Ground: America's War in Vietnam" by Elizabeth Partridge