: marked by careful unremitting attention or persistent application <an assiduous book collector> <tended her garden with assiduous attention>
— as·sid·u·ous·ly adverb
— as·sid·u·ous·ness noun
Examples of ASSIDUOUS
- They were assiduous in their search for all the latest facts and figures.
- The project required some assiduous planning.
Origin of ASSIDUOUS
First Known Use: 1622
Related to ASSIDUOUS
- active, busy, bustling, diligent, employed, engaged, hopping, industrious, laborious, occupied, sedulous, tied-up, working
- idle, inactive, unbusy, unemployed, unoccupied
See Synonym Discussion at busy
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