auburn vs lilac

auburn

adj
  • Of a reddish-brown colour. 

noun
  • A dark reddish-brown colour, often used to describe hair colour. 

lilac

adj
  • Having a pale purple colour. 

noun
  • A flower of the lilac shrub. 

  • A pale purple color, the color of some lilac flowers. 

  • A large shrub of the genus Syringa, especially Syringa vulgaris, bearing white, pale-pink, or purple flowers. 

How often have the words auburn and lilac occurred in a corpus of books? (source: Google Ngram Viewer )