secret

American  

[see-krit] / ˈsi krɪt /

adjective

1. done, made, or conducted without the knowledge of others.

   secret negotiations.

   Synonyms:

   covert, hidden, clandestine

   Antonyms:

   manifest, open

2. kept from the knowledge of any but the initiated or privileged.

   a secret password.

   Synonyms:

   confidential, private

3. faithful or cautious in keeping confidential matters confidential; close-mouthed; discreet.

   Synonyms:

   reticent, secretive, close

4. designed or working to escape notice, knowledge, or observation: the secret police.

   a secret drawer;

   the secret police.

5. secluded, sheltered, or withdrawn.

   a secret hiding place.

6. beyond ordinary human understanding; esoteric.

   Synonyms:

   mysterious, cryptic, occult

7. (of information, a document, etc.)

   1. bearing the classification secret.

   2. limited to persons authorized to use information documents, etc., so classified.

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noun

1. something that is or is kept secret, hidden, or concealed.

2. a mystery.

   the secrets of nature.

3. a reason or explanation not immediately or generally apparent.

4. a method, formula, plan, etc., known only to the initiated or the few: a trade secret.

   the secret of happiness;

   a trade secret.

5. a classification assigned to information, a document, etc., considered less vital to security than top-secret but more vital than confidential, and limiting its use to persons who have been cleared, as by various government agencies, as trustworthy to handle such material.

6. (initial capital letter) a variable prayer in the Roman and other Latin liturgies, said inaudibly by the celebrant after the offertory and immediately before the preface.

idioms

1. in secret, unknown to others; in private; secretly.

   A resistance movement was already being organized in secret.

secret British  

/ ˈsiːkrɪt /

adjective

1. kept hidden or separate from the knowledge of others

2. known only to initiates

   a secret password

3. hidden from general view or use

   a secret garden

4. able or tending to keep things private or to oneself

5. operating without the knowledge of outsiders

   a secret society

6. outside the normal range of knowledge

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noun

1. something kept or to be kept hidden

2. something unrevealed; mystery

3. an underlying explanation, reason, etc, that is not apparent

   the secret of success

4. a method, plan, etc, known only to initiates

5. liturgy a variable prayer, part of the Mass, said by the celebrant after the offertory and before the preface

6. among the people who know a secret

secret More Idioms  

1. see in secret; open secret.

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Other Word Forms

• nonsecret
  adjective
• quasi-secret
  adjective
• secretly
  adverb
• secretness
  noun
• semisecret
  adjective
• supersecret
  noun
• ultrasecret
  adjective

Etymology

Origin of secret

First recorded in 1350–1400; Middle English secrette, from Old French secret, from Latin sēcrētus “hidden,” originally past participle of sēcernere “to secern ”

Explanation

A secret is something you don’t want everybody to know, like your secret crush on the bus driver. A secret can also be a mystery known to only a few — the secret of the lost pyramid. There might be a secret passageway in your basement that only you know about. You could have a secret passion for Japanese anime comics and share that secret with only your closest friends. If you're "in on a secret" — plans for a surprise birthday party, for instance — that means you're in the inner circle of people in the know. Everybody has to keep the secret, or the party won't be a surprise.

Example Sentences

This must be part of the secret sauce — Wyatt’s dedication and consistency.

From Los Angeles Times • May 19, 2026

The secret value needed to be large and negative for the experiment to align with expectations.

From Science Daily • May 18, 2026

At the time, her mysterious relationship with Musk was secret.

From Barron's • May 18, 2026

Each day's route was kept secret until just hours before he set out.

From BBC • May 15, 2026

He’d lowered his voice enough that I had to lean in to hear him, enough to make it obvious that this was an important secret.

From "The Brightwood Code" by Monica Hesse

Related Words

• classified
• covert
• furtive
• hush-hush
• mysterious
• obscure
• private
• secluded
• undercover
• underground
• undisclosed
• unknown
• unpublished