What does the word overture mean?

Usage examples for overture

  1. But in the present overture this essential did not at once appear. – The Salamander by Owen Johnson
  2. When she had at once answered his first subsequent overture with an assent, he had of course been certain that it was so. – Can You Forgive Her? by Anthony Trollope
  3. Gradually all the lights were turned out and the overture commenced. – The Sunny Side of Diplomatic Life, 1875-1912 by Lillie DeHegermann-Lindencrone