engagement vs promise

engagement

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

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

  • Connection or attachment. 

  • An appointment, especially to speak or perform. 

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

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

promise

noun
  • Reason to expect improvement or success; potential. 

  • A transaction between two persons whereby the first person undertakes in the future to render some service or gift to the second person or devotes something valuable now and here to his use. 

  • A placeholder object representing the eventual result of an asynchronous operation. 

  • an oath or affirmation; a vow 

verb
  • To commit to (some action or outcome), or to assure (a person) of such commitment; to make an oath or vow. 

  • To give grounds for expectation, especially of something good. 

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