agreement vs unison

agreement

noun
  • A state whereby several parties share a view or opinion; the state of not contradicting one another. 

  • Rules that exist in many languages that force some parts of a sentence to be used or inflected differently depending on certain attributes of other parts. 

  • A legally binding contract enforceable in a court of law. 

  • An understanding between entities to follow a specific course of conduct. 

unison

noun
  • The state of being in harmony or agreement; harmonious agreement or togetherness, synchronisation. 

  • A sound or note having the same pitch as another, especially when used as the base note for an interval; a unison string. 

  • Identical pitch between two notes or sounds; the simultaneous playing of notes of identical pitch (or separated by one or more octaves). 

  • Two or more voices speaking the same words together. 

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