From Longman Dictionary of Contemporary Englishchemicalchem‧i‧cal1 /ˈkemɪkəl/ ●●● S3 W3 AWL noun [countable] HCa substance used in chemistry or produced by a chemical processtoxic/hazardous/dangerous chemicals the organic chemicals industry synthetic chemicalsCOLLOCATIONSadjectivesdangerous/harmfulMany cleaning products contain chemicals that can be harmful.hazardous (=very dangerous)There are major problems over the disposal of hazardous chemicals.toxic/poisonous (=containing poison)The chemicals that were released were highly toxic.synthetic chemicals (=made by mixing artificial substances)A synthetic chemical is, in theory, identical to that found in nature.organic chemicals (=containing natural substances including carbon)Oil and coal are known as organic chemicals.industrial/agricultural chemicals (=used in industry/in farming)Some deaths from cancer are related to industrial chemicals.verbsuse chemicalsFarmers use chemicals to kill insects that would destroy their crops.produce chemicalsthe dangerous chemicals produced by burning oilbe exposed to chemicalsSome of the troops were exposed to chemicals.chemical + NOUNthe chemical industryThe chemical industry is one of the most important industrial sectors.a chemical plant (=factory producing chemicals)There has been an explosion at a chemical plant in Germany.a chemical fertilizer (=chemicals to help plants grow)Many crops are grown with chemical fertilizers.chemical wastethe risks from pollution and chemical wastechemical weapons (=poisonous chemicals used as weapons)a global treaty banning chemical weaponschemical warfare (=the use of chemical weapons in wars)There is now also the threat of chemical warfare.
Examples from the Corpus
chemical• Folic acid, a B vitamin, reduces heart-attack risks by lowering a potentially deadly blood chemical called homocysteine.• Kitchen chemicals, such as detergents, are bad for nails because they strip away natural oils.• Needles had already been inserted in his arms to deliver the fatal mix of chemicals.• Farmers are moving away from the use of chemicals and pesticides.• Eventually a more effective pump was installed which removed both offensive chemicals and colour.• Because of using the chemicals in the experiments, I was getting a rash.• a highly toxic chemical• Swallow your chemicals, swallow them fast, and get back inside.toxic/hazardous/dangerous chemicals• An initial program may include only the most acutely toxic chemicals.• Stolen chemicals: A car containing hazardous chemicals was stolen in South Hylton, Sunderland.• That fancy motherboard that runs your computer is dipped in toxic chemicals.• Beyond the barrier lay some of the most toxic chemicals known, awaiting destruction by fire.• Some tropical woods such as teak and green-heart contain small amounts of toxic chemicals and also of silica.• The flood of toxic chemicals creates even more serious health problems in this brave new workplace.• Entire coastal bays and lagoons along the coast have been fouled by oil spills and the runoff of toxic chemicals.• Army scatter-spray these toxic chemicals from planes.chemicalchemical2 ●●● W3 AWL adjective [only before noun] HCrelating to substances, the study of substances, or processes involving changes in substances the chemical composition of bleach a chemical analysis of the soil —chemically /-kli/ adverb Chemically, the substances are similar.Examples from the Corpus
chemical• a chemical analysis of the skeletons• For example, the natural arrangement of the chemical elements in Mendeleyev's periodic table has groups of traits reappearing cyclically.• chemical engineering• The hon. Member for Londonderry, East asked about emissions from the chemical incinerator at the Coalite works.• Traditionally, the rare earths have been used as catalysts in the chemical industry and in flints for cigarette lighters.• Samples of rock from them have provided researchers with most of their knowledge of the chemical makeup of the mantle.• In Zurich, stocks eased, led down by the chemical sector.• The quick way is not to use any artificial fertilisers, chemical sprays or dusts.• Rather, it was based on the fact that chemical weapons are not useful for us.Origin chemical2 (1500-1600) Modern Latin chimicus “alchemist”, from Medieval Latin alchimicus, from alchymia; → ALCHEMY