epochal vs seasonal

epochal

adj
  • Of or pertaining to an epoch. 

  • Highly important or significant; monumental, epoch-making. 

seasonal

adj
  • Of, related to, or reliant on a season or period of the year, especially with regard to weather characteristics. 

noun
  • Anything that is seasonal, such as a financial trend, a product for sale, or an employee. 

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