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Synonyms

top-secret

American  
[top-see-krit] / ˈtɒpˈsi krɪt /

adjective

  1. bearing the classification top-secret, the highest level of classified information.

  2. limited to persons authorized to use anything so classified.


top-secret British  

adjective

  1. containing information whose disclosure would cause exceedingly grave damage to the nation and therefore classified as needing the highest level of secrecy and security

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of top-secret

First recorded in 1940–45; top 1 + secret

Explanation

Have you sworn not to reveal the information in a thick file of papers? Then you can describe it as top-secret or classified — it is confidential, and must not be publicized or shared. If you work for the CIA or the FBI some day, you'll likely be responsible for top-secret information. A top-secret mission might mean that you aren't allowed to tell anyone where you're going or what you are doing there. When a government or company classifies something as top-secret, it's either because revealing it could harm people or because it could harm business interests. The recipe for fried chicken at your favorite fast food place? It's top-secret.

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

In 2018, Israel admitted carrying out a top-secret air raid against the site 11 years earlier.

From Barron's Sep. 1, 2026

Still, their top-secret, multiday bash on Cumberland Island, Ga., was a sizable undertaking.

From Los Angeles Times Aug. 4, 2026

It also doesn’t transfer the customer’s intellectual property, which may include top-secret or clinical data.

From MarketWatch Jul. 2, 2026

He’s currently developing a top-secret project with famed music producer Jimmy Iovine.

From The Wall Street Journal May 18, 2026

If I wanted to work on a top-secret space project someday, I couldn’t have any blemishes on my record.

From "The Lions of Little Rock" by Kristin Levine

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