The consequenc­es of epochal events such as wars and great scientific­discoverie­s are not confined to a small geographic­al area as they were in the past.

• 句中“战争”和“重大科学发现”是生词的实例，通过它们我们可以猜出epochal的大致词义“重要的”，这与其确切含义“划时代的”十分接近。