para·​quat ˈper-ə-ˌkwät How to pronounce paraquat (audio)
: a highly toxic contact herbicide containing a salt of a cation [C12H14N2]2+

Examples of paraquat in a Sentence

Recent Examples on the Web The federal government needs to be a partner and can start by banning paraquat as has been done in many other countries. Meagan Flynn, Washington Post, 11 Apr. 2023 In two of the species, resistance to oxidative stress went up when the queen was removed, almost doubling the workers’ chance of surviving treatment with paraquat. Tim Vernimmen, Smithsonian Magazine, 21 Jan. 2022 Kalmuss-Katz said paraquat has also been found to cause kidney and respiratory problems. Bob Egelko, San Francisco Chronicle, 24 Sep. 2021 But sometimes the pigweed can appear to resurrect itself even after an application of paraquat: Nicolet recalled a recent instance in which the weeds appeared to die, only to start growing again a few days later. New York Times, 11 Aug. 2021 The Environmental Protection Agency under President Donald Trump proposed last year to renew U.S. registration of paraquat for 15 years, the renewal period set by law while banning nearly all aerial spraying of the herbicide. Bob Egelko, San Francisco Chronicle, 24 Sep. 2021 This field had been sprayed between plantings with an herbicide containing paraquat. New York Times, 11 Aug. 2021 An investigation by Public Eye, a Swiss NGO, and Unearthed, the journalism branch of Greenpeace, quotes the doctor Shankar Ramchandani, who went on a 2019 hunger strike in Odisha, India to protest paraquat sales. Christine Ro, Forbes, 4 Apr. 2021 Similarly, in South Korea, a ban on the herbicide paraquat was followed by a 50% decrease in suicide deaths from pesticide poisoning from 2011-2013. Katie Hunt, CNN, 9 Sep. 2019 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'paraquat.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


para- + quaternary

First Known Use

circa 1961, in the meaning defined above

Time Traveler
The first known use of paraquat was circa 1961

Dictionary Entries Near paraquat

Cite this Entry

“Paraquat.” Dictionary, Merriam-Webster, Accessed 11 Dec. 2023.

Medical Definition


para·​quat ˈpar-ə-ˌkwät How to pronounce paraquat (audio)
: an herbicide containing a salt of a cation [C12H14N2]2+ that is used especially as a weed killer and that is extremely toxic to the liver, kidneys, and lungs if ingested

More from Merriam-Webster on paraquat

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!