security

American  

[si-kyoor-i-tee] / sɪˈkyʊər ɪ ti /

noun

securities plural

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; see origin at secure, -ity

Explanation

Security means safety, as well as the measures taken to be safe or protected. In order to provide adequate security for the parade, town officials often hire extra guards. A small child will sometimes latch on to a blanket or stuffed animal that gives him or her the feeling of security. Often this word is used in compounds such as a security measure, security check or security guard. The security department in a business is sometimes just called security. If there's a troublesome customer at your work, call security to take him away. In the financial world, a stock or bond is also called a security.

Example Sentences

CEO Matt Kinsella champions quantum applications in national security and has shaped the company around this niche.

From Barron's • May 20, 2026

When Ott was arrested in 2024, Austria's then Chancellor, Karl Nehammer, described the case as "a threat to democracy and our country's national security".

From BBC • May 20, 2026

At the same time, “nuclear is emerging as the only scalable, zero‑carbon baseload option,” amid decarbonization pressures, energy security concerns and AI‑driven power growth, he says.

From The Wall Street Journal • May 20, 2026

The case ended with the IRS formally apologizing to Griffin and pledging to improve data security.

From MarketWatch • May 20, 2026

They arrived in Long Island at a small airport with an empty security line and no other passengers.

From "The Way to Rio Luna" by Zoraida Cordova

Related Words

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