9
creepy(adjective, awful, terrible, dirty, gloom)
9
extreme(adjective, great, severe, offensive, awful)
9
gross(adjective, nasty, awful, terrible, vile)
9
haggish(adjective, dull, appearance, dislike, disgusting)
9
objectionable(adjective, dull, terrible, dirty, disgusting)
9
obnoxious(adjective, appearance, nasty, dislike, unpleasant)
8
evil(adjective, awful, dirty, gloom, badly)
8
flagitious(adjective, awful, terrible, horrible, afraid)
8
grievous(adjective, awful, terrible, horrible, afraid)
8
hair-raising(adjective, awful, terrible, horrible, afraid)
8
unholy(adjective, dislike, unpleasant, awful, terrible)
7
abysmal(adjective, awful, terrible, horrible, afraid)
7
deadly(adjective, awful, terrible, horrible, afraid)
7
direful(adjective, awful, terrible, fear, horrible)
7
dreaded(adjective, awful, terrible, horrible, afraid)
7
enormous(adjective, awful, terrible, horrible, afraid)
7
ferocious(adjective, awful, violent, terrible, horrible)
7
forbidding(adjective, appearance, tough, difficult, terrible)
7
frumpy(adjective, dull, terrible, dirty, disgusting)
7
howling(adjective, awful, terrible, horrible, afraid)
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APASmart Define. (2016). frightful thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/frightful/thesaurus/synonyms
ChicagoSmart Define. 2016. "frightful thesaurus" https://smartdefine.org/frightful/thesaurus/synonyms (accessed September 24, 2026).
HarvardSmart Define 2016, frightful thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/frightful/thesaurus/synonyms>.
MLASmart Define. "frightful thesaurus" 29 March 2016. Web. 24 September 2026. <https://smartdefine.org/frightful/thesaurus/synonyms>