Simple Definition of top secret
: kept completely secret by high government officials
Full Definition of top secret
1 : protected by a high degree of secrecy <a top secret weapon> <a top secret meeting>
2a : containing or being information whose unauthorized disclosure could result in exceptionally grave danger to the nation <top secret messages> — compare confidential, secretb : of or relating to top secret documents <a top secret clearance>
Examples of top secret in a sentence
The mission is top secret.
First Known Use of top secret
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