astringency vs courtesy

astringency

noun
  • That which acts as an astringent, causing contraction of soft tissue to restrict the flow of blood. 

  • An astringent taste. 

courtesy

noun
  • A curtsey. 

  • The life interest that the surviving husband has in the real or heritable estate of his wife. 

  • A polite gesture or remark, especially as opposed to an obligation or standard practice. 

  • Consent or agreement in spite of fact; indulgence. 

  • Polite behavior. 

  • Willingness or generosity in providing something needed. 

adj
  • Supplied free of charge. 

  • Given or done as a polite gesture. 

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