Epochal(adjective)
Used to refer to times or events that are very important because they involve new developments and great change:
Hindi meaning:महत्त्वपूर्ण
Synonyms: Significant, Consequential, Important
Antonyms: Unsubstantial, Unremarkable
Example: The International Monetary Fund played a crucial role in many of the epochal events of the 1990s.
Trick to remember: Poaching ka case epochal hai 
