Simple Definition of assiduous
: showing great care, attention, and effort
Full Definition of assiduous
: marked by careful unremitting attention or persistent application <an assiduous book collector> <tended her garden with assiduous attention>
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
Latin assiduus, from assidēre
First Known Use: 1622
Synonym Discussion of assiduous
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