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English definition of “crucial”

crucial

adjective uk   /ˈkruː.ʃəl/ us  
B2 extremely important or necessary: a crucial decision/question Her work has been crucial to the project's success. [+ that] It is crucial that the problem is tackled immediately.Very important or urgent
crucially
adverb uk   /-i/ us  
Very important or urgent
(Definition of crucial from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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