top-secret

IPA/ˌtɒp ˈsiːkrət/
KK[tˈɑpsˈikrət]IPA/ˌtɑːp ˈsiːkrət/

top-secret — adjective

1. describes information, documents, or plans that are shared with only a very smal

1.adjectiveB2
Definition

describes information, documents, or plans that are shared with only a very small group of trusted people, because revealing them could harm a company, a country, or a project.

Example

The general stored top-secret documents in a locked steel safe.

attributive use: top-secret + noun (documents)

Romi refused to discuss the top-secret project with anyone outside the lab.

Common collocations
  • keep something top-secret
  • remain top-secret
  • top-secret document
  • top-secret information
  • top-secret project
  • top-secret report
  • top-secret file
Synonyms
  • classified

    broader term that covers any level of official secrecy; less specific than top-secret.

  • confidential

    softer and more common in business contexts; does not carry the same sense of extreme danger.

  • restricted

    the lowest level of access control; implies limited distribution rather than absolute secrecy.

Antonyms
  • public

    available to everyone, with no access restrictions at all.

  • unclassified

    officially not secret; used in government and military contexts.

Grammar Patterns

top-secret + noun

be/remain + top-secret

Usage Note

Commonly appears before a noun (top-secret document, top-secret project), but also works after a linking verb: 'The details remain top-secret.' Unlike regular adjectives, it has no comparative or superlative form — something is either top-secret or it is not.

Common Mistakes

The details are very top-secret.
The details are top-secret.
'top-secret' is not gradable, so 'very' should not be used with it.
This is a top secret document.
This is a top-secret document.
When used as a compound adjective before a noun, a hyphen is needed.

2. used in official security systems to label information that would put a country'

2.adjectiveC1
Definition

used in official security systems to label information that would put a country's safety in very serious danger if it became known to people without permission.

Example

Only five high-ranking officials have clearance to read top-secret intelligence files.

collocation: top-secret intelligence files

The leak of top-secret diplomatic cables caused a serious crisis between the two nations.

domain: government/military

Common collocations
  • top-secret intelligence
  • top-secret clearance
  • top-secret documents
  • top-secret operation
  • top-secret briefing
  • top-secret materials
  • top-secret communications
  • top-secret information
Synonyms
  • highly classified

    emphasizes the classification level; less specific about the exact tier.

  • eyes-only

    informal term for documents that only specific individuals may read.

Antonyms
  • declassified

    information that was once secret but has been officially released to the public.

Grammar Patterns

top-secret + noun

Usage Note

This sense belongs to a specific government classification system. Documents marked top-secret are one level above 'secret' and two levels above 'confidential.' Subject is typically a government agency, military body, or authorized contractor.

Common Mistakes

The recipe is top-secret for our restaurant.
The recipe is a closely guarded secret for our restaurant.
The national-security sense should not be used for everyday business secrets.

Word family

Synonym discussion

Sense: adjective/1

All four words describe information that is not available to the general public, but they differ in the level of risk and formality. 'Top-secret' is the strongest — it implies that revealing the information could cause severe damage to a country or organization. 'Secret' (without 'top-') is one tier lower in official classification systems and is also used more loosely in everyday life. 'Classified' is a broad official term for any document placed in a secrecy system, from 'restricted' up to 'top-secret.' 'Confidential' is common in business and healthcare contexts, where a breach would cause moderate harm but not threaten national security. 'Restricted' is the mildest — it simply means access is limited to certain people. For everyday use: if you tell a colleague 'This is top-secret,' you sound dramatic; 'confidential' or 'private' would be more natural.

classified ↗confidential ↗restricted ↗secret ↗

Common collocations

Nouns

Adverbs

Phrases

  • top-secret clearance
  • top-secret classification
  • top-secret level

Etymology

LatinFrenchEnglish

Formed by combining the adjective 'top' (meaning 'highest' or 'foremost') with 'secret' (from Latin 'secretus', meaning 'set apart, hidden'). The compound came into use in the early 20th century, first appearing in government and military classification systems during World War I and becoming standard terminology by World War II.

First known use

1942

1942, in the meaning defined at sense 1