fastness vs oasis

fastness

noun
  • A fortified or secure place; a fortress, a stronghold. 

  • The ability of a dye to withstand fading. 

  • The quality or state of moving quickly; quickness, rapidity, swiftness. 

  • Something used to fasten or tie; a fastener or fastening. 

  • The quality or state of being strongly attached; firmness, secureness, tenacity. 

  • The quality or state of having an extravagant lifestyle or immoral habits. 

oasis

noun
  • A quiet, peaceful place or situation separated from surrounding noise or bustle. 

  • A spring of fresh water, surrounded by a fertile region of vegetation, in a desert. 

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