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English definition of “arduous”


adjective     /ˈɑː.dju.əs/ US  /ˈɑːr.dʒu-/
difficult, needing a lot of effort and energy: an arduous climb/task/journeyComplicated and difficult to doDifficult to understand arduously     /-li/ adverb Complicated and difficult to doDifficult to understand arduousness     /-nəs/ noun [U] Complicated and difficult to doDifficult to understand
(Definition of arduous adjective from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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