duration vs epoch

duration

noun
  • An amount of time or a particular time interval. 

  • The time taken for the current situation to end, especially the current war 

  • A measure of the sensitivity of the price of a financial asset to changes in interest rates, computed for a simple bond as a weighted average of the maturities of the interest and principal payments associated with it. 

epoch

noun
  • A specific instant in time, chosen as the point of reference or zero value of a system that involves identifying instants of time. 

  • A geochronologic unit of hundreds of thousands to millions of years; a subdivision of a period, and subdivided into ages (or sometimes subepochs). 

  • A particular period of history, or of a person's life, especially one considered noteworthy or remarkable. 

  • A notable event which marks the beginning of such a period. 

  • One complete presentation of the training data set to an iterative machine learning algorithm. 

verb
  • To divide (data) into segments by time period. 

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