12
agonizing(adjective, painful, sickness, ache, anguishes)
12
steep(adjective, sharp, course, extreme, quick)
10
aching(adjective, painful, sickness, ache, anguishes)
10
exacting(adjective, dull, hard, tough, severe)
10
excruciating(adjective, painful, sickness, ache, anguishes)
10
piercing(adjective, painful, sickness, ache, anguishes)
10
uncomfortable(adjective, painful, sickness, ache, anguishes)
10
wearying(adjective, dull, difficult, awkward, boring)
9
biting(adjective, painful, sickness, ache, anguishes)
9
energetic(strenuous, challenging)
9
rigorous(adjective, hard, tough, severe, rough)
9
throbbing(adjective, painful, sickness, ache, anguishes)
9
unpleasant(adjective, difficult, harsh, tender, cruel)
9
wearisome(adjective, dull, tough, severe, difficult)
8
intense
8
stiff(adjective, hard, tough, severe, rough)
8
tormenting(adjective, painful, sickness, ache, anguishes)
7
effortful(adjective, hard, great, tough, rough)
7
harrowing(adjective, hard, severe, difficult, tender)
7
hurtful(adjective, painful, sickness, ache, anguishes)
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APASmart Define. (2016). arduous thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/arduous/thesaurus/synonyms
ChicagoSmart Define. 2016. "arduous thesaurus" https://smartdefine.org/arduous/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2016, arduous thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/arduous/thesaurus/synonyms>.
MLASmart Define. "arduous thesaurus" 26 February 2016. Web. 22 September 2026. <https://smartdefine.org/arduous/thesaurus/synonyms>