Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
epoch-making is an adjective meaning "highly significant or important especially bringing about or marking the beginning of a new development or era". It carries one recorded sense.
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”
Definitions, synonyms and semantic relations for epoch-making come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.