adjective. Of utmost importance; of outstanding significance or consequence.

Of moment or consequence; of surpassing importance; critical.

Synonyms Grave, serious.

adjective. Of moment or consequence; very important; weighty

adjective. outstanding in importance

adjective. of unparalleled significance

adjective. of very great significance

"The Australian prime minister also noted what she called the "momentous" upheaval in the Middle East, and pledged her alliance with the United States in condemning Iran's nuclear program, and in a call for an Israeli-Palestinian resolution."

important  significant  

momentously  momentousness  

apprentice  portentous  

crucial  decisive  eventful  excite  far-reaching  

absolute  ascendant  authoritarian  authoritative  authorized