noun ac·e·phate \ˈa-sə-ˌfāt\

Definition of acephate

  1. :  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 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.

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Origin and Etymology of acephate

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

First Known Use: 1972

Seen and Heard

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feeling or affected by lethargy

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