security

American  

[si-kyoor-i-tee] / sɪˈkyʊər ɪ ti /

noun

plural

securities

1. freedom from danger, risk, etc.; safety.

2. freedom from care, anxiety, or doubt; well-founded confidence.

   Synonyms:

   positiveness, certainty, assurance

3. something that secures or makes safe; protection; defense.

   Synonyms:

   safety, safeguard

4. freedom from financial cares or from want.

   The insurance policy gave the family security.

5. precautions taken to guard against crime, attack, sabotage, espionage, etc..

   claims that security was lax at the embassy;

   the importance of computer security to prevent hackers from gaining access.

6. a department or organization responsible for protection or safety.

   He called security when he spotted the intruder.

7. protection or precautions taken against escape; custody.

   The dangerous criminal was placed under maximum security.

8. an assurance; guarantee.

9. Law.

   1. something given or deposited as surety for the fulfillment of a promise or an obligation, the payment of a debt, etc.

   2. one who becomes surety for another.

10. an evidence of debt or of property, as a bond or a certificate of stock.

11. Usually securities. stocks and bonds.

12. Archaic. overconfidence; cockiness.

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adjective

1. of, relating to, or serving as security.

   The company has instituted stricter security measures.

security British  

/ sɪˈkjʊərɪtɪ /

noun

1. the state of being secure

2. assured freedom from poverty or want

   he needs the security of a permanent job

3. a person or thing that secures, guarantees, etc

4. precautions taken to ensure against theft, espionage, etc

   the security in the government offices was not very good

5. (often plural)

   1. a certificate of creditorship or property carrying the right to receive interest or dividend, such as shares or bonds

   2. the financial asset represented by such a certificate

6. the specific asset that a creditor can claim title to in the event of default on an obligation

7. something given or pledged to secure the fulfilment of a promise or obligation

8. a person who undertakes to fulfil another person's obligation

9. the protection of data to ensure that only authorized personnel have access to computer files

10. archaic carelessness or overconfidence

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security Idioms  

More idioms and phrases containing security

• lull into (false sense of security)

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Other Word Forms

• nonsecurity noun
• oversecurity noun
• self-security noun
• subsecurity noun

Etymology

Origin of security

First recorded in 1400–50; late Middle English securytye, securite(e), from Latin sēcūritās; secure, -ity

Example Sentences

A resident in Isfahan said balaclava-clad security forces had set up new checkpoints in the central Iranian city and nearby towns over the weekend.

From The Wall Street Journal • Apr. 3, 2026

The White House said the aim of the tariffs was to reduce national security risks by boosting manufacturing of key medicines in the US.

From BBC • Apr. 2, 2026

"He betrayed the Iranians," said one woman in her 30s, requesting anonymity for security reasons.

From Barron's • Apr. 2, 2026

Seasoned boxing media noted that the security presence felt unusually high for the venue.

From BBC • Apr. 2, 2026

I caught sight of Salzburg again, and I felt a pang of regret that he was the one who had come to the mountain for security talks and not my mom.

From "Glitch" by Laura Martin

Related Words

• bond
• care
• freedom
• guarantee
• insurance
• preservation
• surveillance