overture (n.)youdaoicibaDictYouDict[overture 词源字典]
mid-13c., "opening, aperture;" early 15c. as "an introductory proposal," from Old French overture "opening; proposal" (Modern French ouverture), from Latin apertura "opening," from aperire "to open, uncover" (see overt). Orchestral sense first recorded in English 1660s.[overture etymology, overture origin, 英语词源]