Other forms: insecticides
An insecticide is a chemical that kills insects. Spray insecticide, an insecticide ban, insecticide resistance.
The trouble is that it rarely kills only what you meant: neonicotinoids were restricted in Europe because of the harm to bees. Resistance builds fast, since insects breed quickly, so a chemical that worked ten years ago may do nothing now.
1nouninsecticideA chemical that kills insects.
“The farmer sprayed insecticide on the crops to kill the greenfly.”
insecticide is a chemical.
From insect plus -cide, from Latin caedere, to kill. Insect itself means cut into, from the segmented body.
French
insecticide
English, today
insecticide
From French insecticide, as insect + icide.
Etymology from Wiktionary, CC BY-SA