harbor vs quay

harbor

noun
  • A sheltered expanse of water, adjacent to land, in which ships may anchor or dock, especially for loading and unloading. 

  • Any place of shelter. 

  • A mixing box for materials. 

  • A harbor, even if it is a little harbor, is a good thing, since adventurers come into it as well as go out, and the life in it grows strong, because it takes something from the world, and has something to give in return - Sarah Orne Jewett 

verb
  • To take refuge or shelter in a protected expanse of water. 

  • To drive (a hunted stag) to covert. 

  • To hold or persistently entertain in one's thoughts or mind. 

  • To provide a harbor or safe place for. 

quay

noun
  • A stone or concrete structure on navigable water used for loading and unloading vessels; a wharf. 

verb
  • To land or tie up at a quay or similar structure, especially used in the phrase "quay up". 

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