5
intense
5
resolute
5
steadfast
5
thoroughgoing(adjective, thorough, meticulous, painstaking)
4
ambitious(adjective, work, labour, multitask)
4
ardent
4
close
4
dynamic(adjective, active)
4
exact(adjective, thorough, meticulous, painstaking)
4
finicky(adjective, thorough, meticulous, painstaking)
4
keen(adjective, smart, skillful, nimble-witted)
4
mindful(adjective, thoughtful, sober, considerate, cautious)
4
observant(adjective, thoughtful, sober, considerate, cautious)
4
operose(adjective, work, labour, multitask)
4
pertinacious
4
plodding(adjective, activity, work, labour, multitask)
4
productive(adjective, work, strain, firmness, labour)
4
spirited(adjective, active)
4
tenacious
4
unfailing(adjective, certain, unchanging)
11 years ago|15k views|share |citing 
APASmart Define. (2015). assiduous thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/assiduous/thesaurus/synonyms
ChicagoSmart Define. 2015. "assiduous thesaurus" https://smartdefine.org/assiduous/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2015, assiduous thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/assiduous/thesaurus/synonyms>.
MLASmart Define. "assiduous thesaurus" 14 April 2015. Web. 22 September 2026. <https://smartdefine.org/assiduous/thesaurus/synonyms>