64 entries under thoughtful topic. ×

34
diligent(adjective, activity, work, keen, strain)
31
industrious(adjective, activity, work, keen, strain)
26
sedulous(adjective, activity, work, strain, difficult)
15
attentive(adjective, deliberate, active, alert, careful)
12
busy(adjective, work, keen, intense, energetic)
11
conscientious(adjective, work, tough, strain, exact)
10
studious(adjective, careful, serious, considerate)
9
thorough(adjective, careful, sober, earnest)
8
intent(adjective, activity, lively, caring)
6
alert(adjective, sober, considerate, cautious)
5
eager(adjective, determined, active, serious)
4
mindful(adjective, sober, considerate, cautious)
4
observant(adjective, sober, considerate, cautious)
3
fussy(adjective, deliberate, precise, trivial)
2
precise(sober, cautious, prudent, wary)
2
provident(sober, cautious, prudent, wary)
2
regardful(sober, considerate, cautious, prudent)
2
rigorous(sober, cautious, prudent, wary)
2
serious(adjective, reflective)
1
enthralled(adjective, caring, considerate, responsive)
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APASmart Define. (2015). assiduous thesaurus. Retrieved September 25, 2026, from https://smartdefine.org/assiduous/thesaurus/synonyms
ChicagoSmart Define. 2015. "assiduous thesaurus" https://smartdefine.org/assiduous/thesaurus/synonyms (accessed September 25, 2026).
HarvardSmart Define 2015, assiduous thesaurus, Smart Define, viewed 25 September, 2026, <https://smartdefine.org/assiduous/thesaurus/synonyms>.
MLASmart Define. "assiduous thesaurus" 14 April 2015. Web. 25 September 2026. <https://smartdefine.org/assiduous/thesaurus/synonyms>