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English definition of “security”

security

noun  /sɪˈkjʊər·ɪ·t̬i/ us  

security noun (FREEDOM FROM RISK)

[U] freedom from risk and the threat of change for the worse : financial/job security

security noun (FREE FROM DANGER)

[U] social studies freedom from danger; safety: For security reasons, for the protection of the White House and the president, they felt it necessary to close the avenue. A convicted spy, he sold information that may have damaged our national security. [U] social studies Security is also the group of people responsible for keeping buildings or other areas safe: If anyone gives you trouble, just call security.

security noun (INVESTMENT)

[C usually pl] an investment in a company or in government debt that can be traded on the financial markets

security noun (MONEY)

[U] money you pay someone that can be legally used by that person if your actions cause the person to lose money, but that will be returned to you if it is not used: You have give the landlord an extra month’s rent as security when you sign the lease.
(Definition of security from the Cambridge Academic Content Dictionary © Cambridge University Press)
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