asynchronicity vs synchronism

asynchronicity

noun
  • The extent to which something is asynchronous. 

  • The state of being asynchronous. 

synchronism

noun
  • The tabular arrangement of contemporary events etc. in history. 

  • A temporal relationship between events. 

  • The state of being synchronous. 

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