1. [ verb ] put in motion or move to act
Synonyms: spark trigger set_off touch_off actuate spark_off trigger_off trip

"trigger a reaction" "actuate the circuits"

Related terms: initiate act tripper trigger actuator anticipate happen
2. [ verb ] make active or more active

"activate an old file"

Related terms: inactivate change reactivate activator
3. [ verb ] (chemistry) make more adsorptive; of metals
Related terms: change activation
4. [ verb ] aerate (sewage) so as to favor the growth of organisms that decompose organic matter
Synonyms: aerate
Related terms: change air
5. [ verb ] (physics) make (substances) radioactive
Related terms: change activation
Similar spelling:   activated