What does chlorpyrifos mean?
Chlorpyrifos is a synthetic organophosphate insecticide developed in the mid-1960s and long used to control pests on crops such as corn, soybeans, orchard fruits, and vegetables, as well as in homes and on livestock. Like other organophosphates, it works by inhibiting acetylcholinesterase, an enzyme essential for proper nerve function, which makes it lethal to insects but also potentially harmful to humans and wildlife at sufficient doses. The word functions as an uncountable technical noun, appearing chiefly in scientific literature, regulatory documents, and news reporting. In recent decades chlorpyrifos has become controversial: research has linked prenatal and childhood exposure to neurological and developmental harms, prompting bans or restrictions on food uses in many countries, including a US phase-out of residential use in 2000-2001 and subsequent moves against agricultural applications. Today the term carries strong associations with pesticide safety debates and public-health regulation.
nounA broad-spectrum organophosphate insecticide used to kill pests on crops, in buildings, and on animals; it acts by inhibiting the enzyme acetylcholinesterase in the nervous systems of insects.
- A toxic organophosphate insecticide (chemical name O,O-diethyl O-(3,5,6-trichloro-2-pyridyl) phosphorothioate) used against agricultural and household pests, acting by inhibiting acetylcholinesterase.
"The farm stopped using chlorpyrifos after regulators linked the pesticide to developmental problems in children."
"Residues of chlorpyrifos were detected on several batches of imported fruit."
"The agency's decision to ban chlorpyrifos on food crops followed years of litigation over its health effects."
Chlorpyrifos was one of America's most widely used farm insecticides for decades — until scientists found even tiny exposures could affect children's brain development.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of chlorpyrifos
The name chlorpyrifos is a modern chemical coinage built from descriptive fragments rather than inherited from any older language. It combines "chlor-" from Greek chlōros, meaning pale green, referring to the chlorine atoms in the molecule; "pyri-" from pyridine, the ring compound derived ultimately from Greek pyr, fire; and "-fos" referencing phosphorus, itself from Greek phōsphoros, light-bearing. Such systematic names were constructed by chemists when the compound was developed commercially in the mid-1960s, so its history belongs to twentieth-century industrial chemistry rather than to classical word formation.
How chlorpyrifos is actually used
Chlorpyrifos is a technical, scientific term encountered mainly in agriculture, chemistry, environmental science, journalism about pesticides, and regulatory contexts. It is a mass noun with no plural form in ordinary use. Because of documented health concerns, the word often appears in negative contexts such as bans, restrictions, lawsuits, and exposure studies.
Easily confused with chlorpyrifos
Glyphosate is a herbicide that kills weeds and plants, whereas chlorpyrifos is an organophosphate insecticide that kills insects.