- A guarantee, for example, a mortgage or collateral, intended to ensure an obligation is met
- Documented proof of debt, property ownership, or the entitlement to ownership
- Actions taken to protect from dangers such as spying, tampering, criminal activities, attacks, or escaping
- A body or unit responsible for maintaining safety
- His car was used as security for the loan he took out.
- She has security in the form of stocks and bonds, proving her partial ownership in the company.
- They have implemented strict security measures at the airport to prevent any potential threat.
- The building's security department conducts regular surveillance to maintain the safety of its residents.