反义词是unidentified，例如：

1、He was shot this morning by unidentified intruders at his house.他今天早上在家中被身份不明的闯入者射杀。

2、The painting was sold to an unidentified American dealer.这幅画卖给了一名未披露姓名的美国商人。

3、The document was excerpted from an unidentified FBI file.此文件摘自来源不明的联邦调查局档案。