earth-shattering

(adjective) extremely important or terrible

Example Sentences:

The terrorist attacks were earth-shattering, because the world was different afterwards.

When my boyfriend died in a car accident, it was an earth-shattering event. It took me two years to recover.

From the Blogs:

Earth-shattering moments

Media:

Similar idioms:

1. shatter
2. down-to-earth
3. does not hold water
4. train wreck
5. pull through