What does "security" mean?

Security: That which secures or makes safe; protection; guard; defense. Specifically: (a) Something given, deposited, or pledged, to make certain the fulfillment of an obligation, the performance of a contract, the payment of a debt, or the like; surety; pledge. Those who lent him money lent it on no security but his bare word. Macaulay. (b) One who becomes surety for another, or engages himself for the performance of another's obligation.

Additional senses

  1. 2.An evidence of debt or of property, as a bond, a certificate of stock, etc.; as, government securities.

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