Word
Definitions
01safety and protection
B1 · Intermediate Uncountable noun
n. the state of being safe from danger, harm, or crime.
n. the state of being free from danger or threat, especially regarding physical, national, or digital safety.
“The hotel has high security to make sure all the guests feel safe.”
“National security remains a top priority for the government as they implement new protocols to protect digital infrastructure from cyberattacks.”
Usage
Often used as an uncountable noun when referring to the general state of being safe.
Synonyms
Antonyms
02guards or measures
B1 · Intermediate Uncountable noun
n. the people or systems that protect a place, like a building or airport.
n. the activities, personnel, or equipment involved in protecting a person, building, or organization.
“Security stopped him at the gate because he didn't have his ID card.”
“Airport security has become significantly more stringent over the last decade, requiring passengers to undergo multiple layers of screening.”
Usage
Can be used as a collective noun for the department or staff.
Synonyms
03financial collateral
B2 · Upper Intermediate Uncountable noun Law Formal
n. something valuable you give to a bank to prove you will pay back a loan.
n. an asset or property provided as a guarantee for the fulfilment of an obligation, such as a loan repayment.
“He used his house as security for the business loan.”
“The lender required additional security before approving the mortgage, as the borrower's credit history was considered insufficient.”
Usage
Often takes the preposition 'for'.
Teaching tip
In everyday English, 'collateral' is a common synonym in banking contexts.
Synonyms
04investment asset
C1 · Advanced Countable noun Finance Technical
n. a financial product that can be bought and sold, like a stock or a bond.
n. a tradeable financial asset, such as a share, bond, or option.
“The company is planning to issue new securities to raise money for the project.”
“The regulatory body oversees the trading of government securities to ensure market stability and protect individual investors.”
Usage
Commonly used in the plural form 'securities'.
Teaching tip
This is a very specific professional sense; learners will mostly encounter it in business news or banking.
Synonyms
05feeling of confidence
B2 · Upper Intermediate Uncountable noun
n. a feeling of being happy and safe, without worrying about the future.
n. the state of being free from anxiety or apprehension; emotional or psychological stability.
“Having a permanent job gives her a sense of financial security.”
“Children need a stable home environment to develop a lasting sense of emotional security and self-confidence.”
Usage
Often used in phrases like 'job security' or 'emotional security'.
Synonyms
Antonyms
Collocations
Common phrases and expressions where native English speakers use the word “security” in context.
Verb
01. ensure security
“The government has taken new measures to ensure security at all international airports.”
verb + noun
02. maintain security
“Extra police officers were hired to maintain security during the music festival.”
verb + noun
Noun
03. security system
“We decided to install a modern security system to protect our home while we are away.”
noun + noun
Real-World Examples
“The agreement expresses support for a stronger NATO presence in the Arctic, and Denmark commits to further strengthen its own security posture in the region.” “Google's AI model Gemini autonomously hacked into three companies during a test of its cyber-security capabilities, the company has said, in what is thought to be the first known case of it carrying out such an act.” “A range of delegates to China's flagship defence conference this week expressed fears over the potential for unchecked AI development and technology rivalries to further heighten risks across the global security environment” Etymology
From secure + -ity, from Middle English securite, from Middle French securité (modern sécurité), from Latin sēcūritās, from Latin sēcūrus (“safe, secure”), from sē- (“without”) + cūra (“care”); see cure. Similar to Latin sine cūrā (“without care, carefree”), which led to English sinecure. Doublet of surety.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.
Word family
VERB
NOUN
ADVERB
Related words
Domains
- Exam level
- CambridgeCambridgeCambridge English QualificationsThe exam suite from Cambridge University Press & Assessment, from A1 Movers up to C2 Proficiency. The benchmark names double as CEFR labels.B1 PreliminaryIELTSIELTSInternational English Language Testing SystemThe 0–9 band test co-owned by the British Council, IDP, and Cambridge. Used for university entry, work, and migration.4.0–5.0TOEFL iBTTOEFL iBTTest of English as a Foreign Language, Internet-Based TestETS's academic English test, the standard route for US university admissions. Scored 0–120, with a 1–6 scale since 2026.1–6 scale: 3.0–3.544–71TOEICTOEICTest of English for International CommunicationETS's workplace English test, big in Japan and Korea. Listening & Reading scores 10–990 and tops out at C1.550–784
- Frequency
- Very common
- Level
- B1 · IntermediateOxford
- Updated
- アルファベット
- 読み方の一覧 →
QR code
englishreference.com/q/security
「カタカナ語」 data: JMdict (EDRDG), CC BY-SA 4.0