Momentous

[Couch Potatoe]

Of great importance or significance, especially in having a bearing on future events.

[Lanell]

very important because of effects on future events:

[gusepinax]

of very great significance

[Richarddok]

outstanding in importance

[BertababySog]

of unparalleled significance

[latindictionary]

Important; weighty; of consequence.

[Larrysaelek]

Momentous is an adjective used to describe an event, decision, or change that is very important or significant, particularly because it will have a profound or far-reaching impact in the future. Such events often have enormous implications for the course of circumstances or history.

[Konrador 0]

of moment or consequence; very important; weighty; as, a momentous decision; momentous affairs