security

noun (plural securities)

• 1 [mass noun] the state of being free from danger or threat:the system is designed to provide maximum security against toxic spills job security
• the safety of a state or organization against criminal activity such as terrorism, theft, or espionage:a matter of national security
• procedures followed or measures taken to ensure the security of a state or organization:amid tight security the presidents met in the Colombian resort
• the state of feeling safe, stable, and free from fear or anxiety:this man could give her the emotional security she needed

• 2a thing deposited or pledged as a guarantee of the fulfilment of an undertaking or the repayment of a loan, to be forfeited in case of default.

• 3 (often securities) a certificate attesting credit, the ownership of stocks or bonds, or the right to ownership connected with tradable derivatives.