vacillation vs vagueness

vacillation

noun
  • Indecision in speech or action. 

  • Changing location by moving back and forth. 

vagueness

noun
  • The condition of being unclear; vague. 

  • Something which is vague, or an instance or example of vagueness. 

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