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assiduous

[ uh-sij-oo-uhs ]
/ əˈsɪdʒ u əs /
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See synonyms for: assiduous / assiduously / assiduousness on Thesaurus.com

adjective
constant in application or effort; working diligently at a task; persevering; industrious; meticulous: an assiduous student.
constant; unremitting: assiduous reading.
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Origin of assiduous

First recorded in 1530–40; from Latin assiduus, equivalent to assid(ēre) “to sit near or beside, dwell close to” (see assess) + -uus adjective suffix; see -ous

OTHER WORDS FROM assiduous

as·sid·u·ous·ly, adverbas·sid·u·ous·ness, nounun·as·sid·u·ous, adjectiveun·as·sid·u·ous·ness, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

How to use assiduous in a sentence

British Dictionary definitions for assiduous

assiduous
/ (əˈsɪdjʊəs) /

adjective
hard-working; perseveringan assiduous researcher
undertaken with perseverance and careassiduous editing

Derived forms of assiduous

assiduously, adverbassiduousness, noun

Word Origin for assiduous

C16: from Latin assiduus sitting down to (something), from assidēre to sit beside, from sedēre to sit
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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