15
tremendous(adjective, pain, awful, terrible, fear)
15
ugly(adjective, appearance, dislike, unpleasant, awful)
15
unspeakable(adjective, mean, bad, unpleasant, awful)
14
beastly(adjective, nasty, unpleasant, awful, violent)
14
grim(adjective, appearance, pain, unpleasant, awful)
14
harrowing(adjective, pain, awful, terrible, horrible)
14
terrific(adjective, great, tough, pain, offensive)
13
formidable(adjective, great, tough, terrible, fear)
13
wicked(adjective, offensive, awful, terrible, dirty)
12
fearsome(adjective, fear, alarming)
12
horrific(adjective, nasty, awful, terrible, vile)
12
morbid(adjective, nasty, awful, terrible, gloomy)
12
vicious(adjective, evil, nasty, awful, violent)
11
distasteful(adjective, terrible, dirty, badly, scary)
11
dread(adjective, awful, terrible, horrible, afraid)
11
grotesque(adjective, appearance, evil, dislike, disgusting)
11
lurid(adjective, evil, unpleasant, awful, terrible)
11
odious(adjective, awful, terrible, horrible, afraid)
10
cruel(adjective, appearance, evil, unpleasant, awful)
10
wretched(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>