security

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Freedom from risk or danger; safety.
• noun Freedom from doubt, anxiety, or fear; confidence.
• noun Something that gives or assures safety, as.
• noun A group or department of private guards.
• noun Measures adopted by a government to prevent espionage, sabotage, or attack.
• noun Measures adopted, as by a business or homeowner, to prevent a crime such as burglary or assault.
• noun Measures adopted to prevent escape.
• noun Something deposited or given as assurance of the fulfillment of an obligation; collateral.
• noun One who undertakes to fulfill the obligation of another; a surety.
• noun A financial instrument, such as a stock or bond, representing rights of ownership or creditorship and often traded in secondary markets.

from The Century Dictionary.

• noun The state of being secure.
• noun Freedom from annoyance, harm, danger, or loss; safety.
• noun That which secures or makes safe; protection; defense; guard.
• noun A guaranty or pledge; something given or deposited as surety for the fulfilment of a promise or an obligation, the payment of a debt, or the like.
• noun A person who engages or pledges himself for the performance of another's obligations; one who becomes surety for another.
• noun An evidence of debt or of property, as a bond or a certificate of stock: as, government securities.

from the GNU version of the Collaborative International Dictionary of English.

• noun The condition or quality of being secure; secureness.
• noun Freedom from apprehension, anxiety, or care; confidence of power or safety; hence, assurance; certainty.
• noun Hence, carelessness; negligence; heedlessness.
• noun Freedom from risk; safety.
• noun That which secures or makes safe; protection; guard; defense.
• noun 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.
• noun One who becomes surety for another, or engages himself for the performance of another's obligation.
• noun An evidence of debt or of property, as a bond, a certificate of stock, etc..

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun uncountable The condition of not being threatened, especially physically, psychologically, emotionally, or financially.
• noun countable Something that secures.
• noun An organization or department responsible for providing security by enforcing laws, rules, and regulations as well as maintaining order.
• noun law Something that secures the fulfillment of an obligation or law.
• noun law Freedom from apprehension.
• noun finance Proof of ownership of stocks, bonds or other investment instruments.W
• noun finance property temporarily relinquished to guarantee repayment of a loan.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun property that your creditor can claim in case you default on your obligation
• noun the state of being free from danger or injury
• noun a department responsible for the security of the institution's property and workers
• noun freedom from anxiety or fear
• noun an electrical device that sets off an alarm when someone tries to break in
• noun a formal declaration that documents a fact of relevance to finance and investment; the holder has a right to receive interest or dividends
• noun a guarantee that an obligation will be met
• noun measures taken as a precaution against theft or espionage or sabotage etc.
• noun defense against financial failure; financial independence