ac·​e·​phate ˈa-sə-ˌfāt How to pronounce acephate (audio)
: an organophosphate insecticide C4H10NO3PS that is used to control insects (such as aphids and thrips) on cultivated crops and ornamental plants
Orthene, the brand name for acephate, is both a contact spray and a systemic organophosphate that acts as a nerve poison.Anne Raver, New York Times, 2 Apr. 1992

Note: Acephate is typically available as a powder, dust, or spray or as granules. Like other organophosphate insecticides, acephate functions by inhibiting the action of the enzyme acetylcholinesterase.

Word History


probably from acetyl + phosphoramidothioate, parts of its earlier systematic name

First Known Use

1972, in the meaning defined above

Time Traveler
The first known use of acephate was in 1972

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Cite this Entry

“Acephate.” Dictionary, Merriam-Webster, Accessed 15 Apr. 2024.

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