iceberg vs serene

iceberg

noun
  • A huge mass of ocean-floating ice which has broken off a glacier or ice shelf 

  • An aloof person. 

  • An impending disastrous event whose adverse effects are only beginning to show, in reference to one-tenth of the volume of an iceberg being visible above water. 

serene

verb
  • To make serene. 

noun
  • Serenity; clearness; calmness. 

  • A fine rain from a cloudless sky after sunset. 

adj
  • Without worry or anxiety; unaffected by disturbance. 

  • Used as part of certain titles, originally to indicate sovereignty or independence. 

  • Calm, peaceful, unruffled. 

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