'Epochal' definitions:

Definition of 'epochal'

From: WordNet
adjective
Highly significant or important especially bringing about or marking the beginning of a new development or era; "epochal decisions made by Roosevelt and Churchill"; "an epoch-making discovery" [syn: epochal, epoch-making]

Definition of 'Epochal'

From: GCIDE
  • Epochal \Ep"o*chal\, a. Belonging to an epoch; of the nature of an epoch. "Epochal points." --Shedd. [1913 Webster]