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

He went home to St. Louis, joined the antiwar movement, and died at 39 from exposure to Agent Orange, leaving behind a wife and five kids.

From Los Angeles Times • Apr. 8, 2026

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

More than half of that spraying involved the dioxin-contaminated defoliant Agent Orange.

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 told her the insignia on his uniform meant he was a crewmember on a helicopter that sprayed Agent Orange.

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