›classified documents and information are officially kept secret and can only be seen by people who have high authority or special permission: Security employees discovered that classified information and passwords had been leaked onto the internet.classified evidence/material/recordsHe was caught taking highly classified documents from the National Archives.
›[before noun]relating to the small advertisements in newspapers, magazines, or on websites that offer jobs or to sell or buy things: The help-wanted classified sections are overflowing with ads for managers.
›used to describe information that is arranged by type: Classified data will increase 50% a year as more economies begin using broadband technology.The classified catalogue tells you which publications on a particular subject are available in the library.