noun
rat poison; rodenticide
A substance used to kill rats and other rodents. Common in pest control contexts.
倉庫に殺鼠剤を置いてネズミを駆除した。
We placed rat poison in the warehouse to exterminate the rats.
Compound of 殺鼠 (sasso, 'rat killing') + 剤 (zai, 'agent, drug').