Definitions

1. verb

to remove or get rid of rats, especially from a building or area

“The exterminator was hired to derat the old warehouse before renovation.”

2. verb, transitive

to remove or kill a rat or rats

“The farmer derated the field by killing the pests that had infested the crops.”

3. noun

the act of removing or getting rid of rats

“The deratting of the building was a major undertaking, requiring specialized equipment and personnel.”