[mass noun] A crystalline synthetic organophosphorus compound used in solution as an insecticide.
- ‘The major OP insecticides used include acephate, azinphos methyl, chlorpyrifos, dimethoate, disulfoton, fenamiphos, and phosmet.’
- ‘In the past, the grass mites in most areas of the state have been controlled reasonably well with dimethoate, which is the least expensive product.’
- ‘Consider alternating synthetic pyrethroids such as permethrin or fenvalerate to organophosphates such as stirofos, dimethoate, or fenthion to carbamates such as methomyl.’
- ‘While methyl parathion is more acutely toxic than the other two OPs, over time a child's chronic exposure to dimethoate and acephate can be just as dangerous.’
- ‘Other insecticides have a narrower range of activity, such as dimethoate and Metasystox-R, which are toxic primarily to sucking pests such as aphids.’
1960s: from di- ‘two’+ methyl + thio- + -ate.
We take a look at several popular, though confusing, punctuation marks.