nameless       
adjective uk/ˈneɪm.ləs/ us/ˈneɪm.ləs/
 无名的;不知名的
having no name, or having a name that is not known
  a nameless soldier 无名战士 
 the nameless author of a medieval text 中世纪文本的佚名作者 
 Idiom   
who shall remain namelessidiom  humorous (说起某人做的坏事时)不便说出其名的
used when you are telling people about a bad thing that someone else has done
  One boy, who shall remain nameless, has been late every day this week. 有一个男孩本周每天都迟到,这里就不说他的名字了。