paraquat

American  

[par-uh-kwaht] / ˈpær əˌkwɑt /

noun

Chemistry.

1. a toxic herbicide, C 1 2 H 1 4 N 2 ⋅2CH 3 SO 4 , applied to food and flower crops and to highway borders as a defoliant and weed-killer.

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Paraquat British  

/ ˈpærəˌkwɒt /

noun

1. a yellow extremely poisonous soluble solid used in solution as a weedkiller

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paraquat Scientific  

/ păr′ə-kwŏt′ /

1. A toxic compound used as a herbicide, especially in its colorless, dichloride form (C ₁₂ H ₁₄ Cl ₂ N ₂) or in its yellow, bismethyl sulfate form (C ₁₄ H ₂₀ N ₂ O ₈ S ₂). Paraquat is used primarily to control grass and weeds. Its use in the United States is restricted because of its high level of toxicity.

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Etymology

Origin of paraquat

1960–65; para- ¹ + quat(ernary), in reference to the bond between the two pyridyl groups, which is in the para position with respect to their quaternary nitrogen atoms

Example Sentences

“We paid thousands of dollars to have it analyzed. … I mean, the paraquat thing was totally scientifically wrong.”

From Slate • Dec. 23, 2025

The federal government banned the use of the weedkiller paraquat on golf courses in 2021.

From The Wall Street Journal • Oct. 31, 2025

“We would like to stress that paraquat is safe when used as directed,” Das said.

From Los Angeles Times • Apr. 8, 2024

A recent Los Angeles Times report documenting concerns about paraquat highlighted one of more than 3,600 lawsuits that have been filed in state and federal courts seeking damages related to exposure to the product.

From Los Angeles Times • Apr. 8, 2024

But recent research has found that farmworkers and low-income Latino people are disproportionately exposed to paraquat in their communities.

From Los Angeles Times • Apr. 8, 2024

Related Words

• defoliant
• fungicide
• insecticide
• pesticide