1.A secret word or phrase which you say to show that you are a friend not an enemy.
你要说的某个密字或短语,籍此表明你是朋友,而不是敌人。
2.a secret word or phrase that one uses to gain admittance or access to information
口令,暗号某人用来得以进入或获得信息所使用的秘密的单词或短语