understanding vs unison

understanding

noun
  • An informal contract; mutual agreement. 

  • Opinion, judgement or outlook. 

  • A reconciliation of differences. 

  • The act of one that understands or comprehends; comprehension; knowledge; discernment. 

  • Sympathy. 

  • Reason or intelligence, ability to grasp the full meaning of knowledge, ability to infer. 

adj
  • Showing compassion, tolerance, and forbearance. 

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 understanding and unison occurred in a corpus of books? (source: Google Ngram Viewer )