working very hard and taking great care that everything is done as well as it can be synonym diligent one of the most assiduous members of the team their assiduous efforts and attention to detail She was assiduous in her duties.
NAmE//ˌæsəˈduət̮i//, NAmE//æsəˈdʒuət̮i//
noun [uncountable] He worked assiduously to earn the money for his son's education.See assiduous in the Oxford Advanced Learner's Dictionary
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