grounds vs vindication

grounds

noun
  • Basis or justification for something. 

  • The sediment at the bottom of a liquid, or from which a liquid has been filtered. 

  • The collective land areas that compose a larger area. 

vindication

noun
  • Evidence, facts, statements, or arguments that justify a claim or belief. 

  • The act of vindicating or the state of being vindicated. 

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