104 entries under difficult topic. ×

60
mighty(adjective, feature, characteristic, strong, tough)
46
tremendous(adjective, feature, characteristic, great)
43
heavy(adjective, feature, characteristic, tough, severe)
40
colossal(adjective, feature, characteristic, great, tough)
39
herculean(adjective, feature, characteristic, tough, severe)
34
powerful(adjective, strong, tough, overwhelming)
22
intimidating(adjective, awful, horrible, shocking)
20
awesome(adjective, great, tough, wonderful)
13
onerous(adjective, tough, severe, difficulty)
13
terrible(adjective, appearance, bad, great, nasty)
13
arduous(adjective, tough, severe, difficulty, rough)
12
tough(adjective, strong, severe, difficulty, rough)
12
impressive(adjective, tough, awful, wonderful)
12
laborious(adjective, tough, severe, difficulty, rough)
11
difficult(adjective, hard, tough, severe, evil)
10
hard(adjective, tough, severe, evil, difficulty)
10
burdensome(adjective, tough, severe, heavy)
10
strenuous(adjective, tough, severe, rough)
9
rough(adjective, hard, tough, nasty)
8
severe(adjective, appearance, great, tough)
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APASmart Define. (2015). formidable thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/formidable/thesaurus/synonyms
ChicagoSmart Define. 2015. "formidable thesaurus" https://smartdefine.org/formidable/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2015, formidable thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/formidable/thesaurus/synonyms>.
MLASmart Define. "formidable thesaurus" 17 July 2015. Web. 20 September 2026. <https://smartdefine.org/formidable/thesaurus/synonyms>