Operating in a hidden or confidential manner:
Containing information, the unauthorized disclosure of which poses a threat to national security.
Kept within certain limits; limited:
A classified is defined as an ad in a paper.
Secret, not spoken of (spoken of only in hushed whispers between insiders).
Find another word for top-secret. In this page you can discover 12 synonyms, antonyms, idiomatic expressions, and related words for top-secret, like: secret, confidential, restricted, classified, highly classified, kgb, us-air-force, kept quiet, hush-hush, supersecret and under security restrictions.