pɹəˈtɛkʃən sɪˈkjʊəɹəti səˈkjɔɹ.ɪˌti ˈʃʊəɹɪti ˈʃʊɹəti measures taken as a precaution against theft or espionage or sabotage etc. military security has been stepped up since the recent uprising an electrical device that sets off an alarm when someone tries to break in a guarantee that an obligation will be met freedom from anxiety or fear the watch dog gave her a feeling of security a department responsible for the security of the institution's property and workers the head of security was a former policeman defense against financial failure; financial independence his pension gave him security in his old age insurance provided protection against loss of wages due to illness property that your creditor can claim in case you default on your obligation bankers are reluctant to lend without good security a formal declaration that documents a fact of relevance to finance and investment; the holder has a right to receive interest or dividends he held several valuable securities the state of being free from danger or injury we support the armed services in the name of national security