416 entries under adjective topic. ×

5
all-powerful(tough, difficult, overwhelming, prevailing)
5
complex(hard, difficult, delicate, heavy)
5
direful
5
dismaying(difficult, horrible, overwhelming, terrifying)
5
exacting(tough, severe, rough, difficult)
5
grisly(appearance, awful, terrible, shocking)
5
gruesome(appearance, awful, terrible, shocking)
5
harsh(hard, great, severe, rough)
5
indomitable(difficult, overwhelming)
5
influential(powerful, prevailing, commanding)
5
labored(tough, severe, difficult, heavy)
5
stiff(great, tough, severe, difficult)
5
sturdy(strong, prevailing, influential, commanding)
5
ticklish(bad, hard, tough, difficult)
5
titan(feature, characteristic, size)
5
tricky(hard, tough, difficult, complex)
5
troublesome(hard, tough, severe, evil)
5
unnerving
4
astonishing(awful, wonderful, amazing, grand)
4
astounding(great, awful, terrible, grand)
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APASmart Define. (2015). formidable thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/formidable/thesaurus/synonyms
ChicagoSmart Define. 2015. "formidable thesaurus" https://smartdefine.org/formidable/thesaurus/synonyms (accessed September 24, 2026).
HarvardSmart Define 2015, formidable thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/formidable/thesaurus/synonyms>.
MLASmart Define. "formidable thesaurus" 17 July 2015. Web. 24 September 2026. <https://smartdefine.org/formidable/thesaurus/synonyms>