coincidental vs isochronous

coincidental

adj
  • Happening or existing at the same time. 

  • Occurring as or resulting from coincidence. 

isochronous

adj
  • Happening at the same time; simultaneous. 

  • Happening at regular intervals; isochronal. 

  • of or pertaining to data associated with time-sensitive applications. 

  • Of or pertaining to the use of clocks derived from the same clock reference. 

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