epoch-making vs epochal

epoch-making and epochal both are adjectives.

Word	Noun	Adjective	Verb	Adverb
epoch-making	No	Yes	No	No
epochal	No	Yes	No	No

As adjectives, epoch-making and epochal are synonyms defined as:

epoch-making and epochal: highly significant or important especially bringing about or marking the beginning of a new development or era

epoch-making (adjective)	epochal (adjective)
highly significant or important especially bringing about or marking the beginning of a new development or era	highly significant or important especially bringing about or marking the beginning of a new development or era