59 entries under heavy topic. ×

5
exacting(adjective, tough, severe, rough, difficult)
5
harsh(adjective, hard, great, severe, rough)
5
labored(adjective, tough, severe, difficult)
5
ticklish(adjective, bad, hard, tough, difficult)
4
hairy(adjective, bad, severe, rough, difficult)
4
sticky(adjective, tough, rough, difficult)
3
complicated(adjective, hard, tough, severe, rough)
3
oppressive(adjective, difficult)
3
painful(adjective, hard, tough, severe, difficult)
3
rigorous(adjective, hard, tough, severe, rough)
3
taxing(adjective, hard, tough, severe, rough)
3
wearing(adjective, tough, rough, difficult)
3
wearying(adjective, tough, rough, difficult)
3
wicked(adjective, bad, nasty, delicate, unpleasant)
2
abstruse(hard, intense, fierce, tricky)
2
backbreaking(adjective, hard, tough, severe, rough)
2
delicate(bad, hard, difficult, complex)
2
distressing(adjective, bad, tough, severe, rough)
2
exhausting(adjective, hard, tough, severe, rough)
2
grinding(adjective, tough, severe, rough, difficult)
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APASmart Define. (2015). formidable thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/formidable/thesaurus/synonyms
ChicagoSmart Define. 2015. "formidable thesaurus" https://smartdefine.org/formidable/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2015, formidable thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/formidable/thesaurus/synonyms>.
MLASmart Define. "formidable thesaurus" 17 July 2015. Web. 22 September 2026. <https://smartdefine.org/formidable/thesaurus/synonyms>