cistern vs dimple

cistern

noun
  • A cisterna. 

  • The vessel surrounding the condenser in a steam engine. 

  • In a flush toilet, the container in which the water used for flushing is held; a toilet tank. 

  • A reservoir or tank for holding water, especially for catching and holding rainwater for later use. 

dimple

noun
  • A small depression or indentation in a surface. 

  • Specifically, a small natural depression on the skin, especially on the face near the corners of the mouth. 

verb
  • To create a dimple in. 

  • To form dimples; to sink into depressions or little inequalities. 

  • To create a dimple in one's face by smiling. 

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