What does the word subtle mean?

Usage examples for subtle

  1. Manon was there under false pretences, her presence a subtle insult to Miss Jones. – The Nest, The White Pagoda, The Suicide, A Forsaken Temple, Miss Jones and The Masterpiece by Anne Douglas Sedgwick
  2. Kendricks must have seen it too, for he began at once to save her from herself, with all his subtle generosity, and to turn her shame to praise. – An Open-Eyed Conspiracy--An Idyl of Saratoga by William Dean Howells
  3. All were gripped by the subtle atmosphere of things. – The Kangaroo Marines by R. W. Campbell