epoch making

/ˈɛpəkˌmeɪkɪŋ/
adjective
  1. So important or new that it marks the beginning of a new period in history or in a particular field.
    • The invention of the printing press was an epoch-making event that changed how knowledge was shared.
    • Many consider the first moon landing to be an epoch-making achievement for all of humanity.
    • Her epoch-making research on climate change won her the Nobel Prize.