1 (used about a person) whose name is not known or made public （指人）不透露姓名的，匿名的；姓名不详的: An anonymous caller told the police that a robbery was going to take place. 警方收到匿名电话，说将会发生抢劫案。

2 done, written, etc by sb whose name is not known or made public （指物）不具名的，匿名的: He received an anonymous letter. 他收到一封匿名信。 ➔anonymously adv