momentous
adj.adj. very important because it will have a big effect on the future. You use this to describe a major event or decision.
adj. of great importance or significance, especially in its bearing on future events. Often used to describe historical turning points or life-changing decisions.
The two countries signed a momentous peace treaty today.
Graduating from university is a momentous occasion that marks the start of a new chapter in life.
The discovery of the new vaccine was a momentous achievement that promised to alter the course of global public health for generations to come.
From moment (“weight, importance”) + -ous.
Typically used as an attributive adjective before a noun like 'decision', 'occasion', or 'event'.
a momentary decisiona momentous decisionLearners confuse 'momentous' (important) with 'momentary' (lasting only a short time).