congruency vs sync

congruency

noun
  • The state of being congruent 

  • The quality of agreeing; being suitable and appropriate 

sync

noun
  • Harmony. 

  • A music synchronization license, allowing the music to be synchronized with visual media such as films. 

verb
  • To synchronize, especially in the senses of data synchronization, time synchronization, or synchronizing music with video. 

  • To flush all pending I/O operations to disk. 

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