C1 adjective ˌmɒn.jʊˈmɛn.təl
monumental
极其重要的,巨大的或纪念性的
Meaning
Great in importance, extent, or size; exceptionally great; forming or serving as a monument.
Example
The discovery of electricity was a monumental achievement.
电的发现是一次纪念碑式的成就。