95 entries under dreadful topic. ×

46
tremendous(adjective, feature, characteristic, great, difficult)
26
fearful(adjective, great, awful, fear, horrible)
18
frightful(adjective, great, tough, terrible, fear)
13
terrible(adjective, appearance, bad, great, nasty)
12
appalling(adjective, bad, great, tough, fear)
10
menacing(adjective, bad, tough, severe, unpleasant)
9
rough(adjective, hard, tough, nasty, difficult)
9
shocking(adjective, appearance, bad, great, unpleasant)
8
dread
8
horrible(adjective, great, tough, unpleasant, awful)
7
fierce(adjective, great, tough, heavy, horrible)
6
dangerous(adjective, hard, tough, severe, evil)
6
serious(adjective, bad, hard, difficult, unpleasant)
6
threatening(adjective, tough, severe, unpleasant, important)
5
grisly(adjective, appearance, awful, terrible, shocking)
5
gruesome(adjective, appearance, awful, terrible, shocking)
5
troublesome(adjective, hard, tough, severe, evil)
4
fell(adjective, tough, severe, unpleasant, important)
4
forbidding(adjective, appearance, tough, unpleasant, terrible)
4
impregnable(adjective, horrible, terrifying)
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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>