epochal
epoc·hal
adjective
1.
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”
Origin
From epoch + -al.
WordNet 2.1 (Princeton University). Wiktionary (CC BY-SA). CMU Pronouncing Dictionary. WordNet 2.1 Copyright Princeton University. All rights reserved. Wiktionary content is available under the Creative Commons Attribution-ShareAlike Licence.