activates
v. B2 Upper Intermediate US //ˈæktəˌveɪts// UK //ˈæktɪvˌeɪts// ac·ti·vates
v. to make something start working or to turn a system on. You use this when you press a button or enter a code to begin a process.
v. to cause a device, system, or chemical process to begin operating. Transitive — requires a direct object such as a mechanism, alarm, or biological pathway.
The motion sensor activates the lights automatically.
Entering the correct security code activates the alarm system and unlocks the main entrance.
The presence of specific antibodies in the bloodstream activates a complex immune response designed to neutralise the invading pathogen before it can replicate further.
Usage
The verb is transitive and takes a direct object.