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.

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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

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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.

Example Sentences

See Examples For:

top-secret

During the war, the government handed it to a top-secret military intelligence unit, and engineers wired it with hidden microphones throughout -- even in the garden.

From Barron's ● Aug. 5, 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

According to federal charging papers, Van Dyke used his knowledge of top-secret operations on Maduro's removal to trade on Polymarket.

From BBC ● Apr. 28, 2026

“But the thing is—it’s like when Margo would ask you to do top-secret stuff. We re in the same situation here.”

From "Paper Towns" by John Green