What does the word indigo mean?

Usage examples for indigo

  1. I however preferred to remain as I was; and many of the people slept around the tents upon heaps of indigo plant, making fires for themselves from the straw. – Byeways in Palestine by James Finn
  2. 1 cent, shades of indigo blue. – History of the Postage Stamps of the United States of America by John Kerr Tiffany
  3. Instantly the world becomes indigo. – Two Years in the French West Indies by Lafcadio Hearn