Classified

clas·si·fied

adjective /ˈklasəˌfīd/ 

Arranged in classes or categories - a classified catalog of books

(of newspaper or magazine advertisements or the pages on which these appear) Organized in categories according to what is being advertised

(of information or documents) Designated as officially secret and to which only authorized people may have access - classified information on nuclear experiments

noun /ˈklasəˌfīd/ 

Small advertisements placed in a newspaper and organized in categories