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English definition of “momentous”

momentous

adjective uk   /məˈmen.təs/ us    /-t̬əs/
very important because of effects on future events: the momentous news of the president's death Whether or not to move overseas was a momentous decision for the family.Very important or urgent
momentously
adverb uk   /-li/ us  
Very important or urgent
momentousness
noun [U] uk   /-nəs/ us  
ImportanceUseful or advantageous
(Definition of momentous from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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