surety (n.)youdaoicibaDictYouDict[surety 词源字典]
c. 1300, "a guarantee, promise, pledge, an assurance," from Old French seurté "a promise, pledge, guarantee; assurance, confidence" (12c., Modern French sûreté), from Latin securitatem (nominative securitas) "freedom from care or danger, safety, security," from securus (see secure (adj.)). From late 14c. as "security, safety, stability; state of peace," also "certainty, certitude; confidence." Meaning "one who makes himself responsible for another" is from early 15c. Until 1966, the French national criminal police department was the Sûreté nationale.[surety etymology, surety origin, 英语词源]