2
straining
2
tall(adjective, easy)
2
terrible(adjective, hard, tough, severe, rough)
2
testing(adjective, tough, severe, difficult, violent)
2
threatening(hard, tough, severe, offensive, weighty)
2
titanic(tough, severe, painful, problematic, trying)
2
uninteresting(adjective, dull, boring, tedious, dreary)
2
unpleasant(hard, severe, difficult, tender, offensive)
2
unremitting
2
unsparing(adjective, tough, rough, difficult, heavy)
2
unwavering
2
vexatious(adjective, dull, difficult, tender, boring)
2
working(adjective, working)
2
worrying(adjective, tough, severe, important, significant)
2
zealous
1
abstruse
1
alarming(hard, severe, offensive, distressing, upsetting)
1
all-out
1
annoying(adjective, dull, boring, tedious, dreary)
1
ardent
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APASmart Define. (2016). laborious thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/laborious/thesaurus/synonyms
ChicagoSmart Define. 2016. "laborious thesaurus" https://smartdefine.org/laborious/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2016, laborious thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/laborious/thesaurus/synonyms>.
MLASmart Define. "laborious thesaurus" 26 February 2016. Web. 23 September 2026. <https://smartdefine.org/laborious/thesaurus/synonyms>