engagement vs vow

engagement

noun
  • The period of time when marriage is planned or promised. 

  • The point at which the fencers are close enough to join blades, or to make an effective attack during an encounter. 

  • Connection or attachment. 

  • The feeling of being compelled, drawn in, connected to what is happening, interested in what will happen next. 

  • An appointment, especially to speak or perform. 

  • In any situation of conflict, an actual instance of active hostilities. 

vow

noun
  • A solemn promise to perform some act, or behave in a specified manner, especially a promise to live and act in accordance with the rules of a religious order. 

  • A declaration or assertion. 

verb
  • To declare publicly that one has made a vow, usually to show one's determination or to announce an act of retaliation. 

  • To make a vow; to promise. 

  • To make a vow regarding (something). 

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