activation       
noun [ U ] uk/ˌæk.tɪˈveɪ.ʃən/ us/ˌæk.təˈveɪ.ʃən/
 激活
the act of making something start or making it start working
  The false activation of an alarm is a serious matter. 误触警报是很严重的事。 
 You will be sent an account activation email. 你会收到一封帐户激活邮件。 
 See: activate
 - More examples
 - The accident was caused by the unneccessary activation of a fire extinguisher.
 - A mayday call may result in the activation of a lifeboat.
 - Type the activation code into your new phone.