Insecticide
Pesticide
noun
What kills insects with one dose? That's an insecticide or a pesticide.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
この農場では殺虫剤の使用は厳禁です。
The use of insecticides is strictly prohibited on this farm.
殺虫剤は人体に入ると危険です。
Pesticides are dangerous if they enter the human body.
蛍は昆虫なので、寒さや殺虫剤に弱い。
Because fireflies are insects, they are vulnerable to cold and insecticides.