ac·ti·vate 
/ˈæktəˌveɪt/ verb
ac·ti·vates; ac·ti·vat·ed; ac·ti·vat·ing /ˈæktəˌveɪt/ verb [+ obj] 1 : to make (something) active or more active: such as a : to cause (a device) to start working
▪ Touch the screen to activate the system. ▪ activate and then deactivate a mechanism ▪ A loud alarm was activated [=set off] when he opened the door. ▪ The camera is activated by pushing a button. ▪ The bomb was activated by remote control.
b chemistry : to cause (a chemical reaction or natural process) to begin
▪ Sunlight activates a chemical reaction in the plant's leaves. ▪ vitamins that activate the growth of new cells 2 chiefly US : to order (soldiers) to serve in a war
▪ The President has activated the reserves. ▪ activate the troops ▪ Our military unit was activated [=called into action] soon after the start of the war.
▪ Touch the screen to activate the system. ▪ activate and then deactivate a mechanism ▪ A loud alarm was activated [=set off] when he opened the door. ▪ The camera is activated by pushing a button. ▪ The bomb was activated by remote control.
b chemistry : to cause (a chemical reaction or natural process) to begin
▪ Sunlight activates a chemical reaction in the plant's leaves. ▪ vitamins that activate the growth of new cells
▪ The President has activated the reserves. ▪ activate the troops ▪ Our military unit was activated [=called into action] soon after the start of the war.
— ac·ti·va·tion /ˌæktəˈveɪʃən/ noun [noncount]
/ˌæktəˈveɪʃən/ noun [noncount]
