What does the word colour mean?

Usage examples for colour

  1. " You look a bit off- colour, Mary. – Over the Sliprails by Henry Lawson
  2. " If she had but a little more colour, my dear Richard! – The Complete Project Gutenberg Works of George Meredith by George Meredith
  3. It was a matter of colour, and she was quite right. – Melbourne House by Elizabeth Wetherell