3
ill favoured(adjective, appearance, dislike, terrible, dirty)
3
immane(adjective, awful, terrible, horrible, afraid)
3
indecent(adjective, dislike, horrible, ugly, yuck)
3
insupportable(adjective, endured)
3
intolerable(adjective, endured)
3
menacing
3
mortal(adjective, awful, terrible, horrible, afraid)
3
off-putting(adjective, terrible, dirty, badly, scary)
3
ominous(appearance, awful, terrible, immoral, atrocious)
3
outrageous(adjective, dislike, horrible, ugly, yuck)
3
parlous(adjective, awful, terrible, horrible, afraid)
3
perishing(adjective, awful, terrible, horrible, afraid)
3
piercing(adjective, endured)
3
scarey(adjective, awful, terrible, horrible, afraid)
3
scathing(adjective, awful, terrible, horrible, afraid)
3
severe(adjective, appearance, great, terrible, extreme)
3
shameful(adjective, dislike, unpleasant, awful, disgusting)
3
sinister(adjective, appearance, awful, terrible, dreadful)
3
splitting(adjective, awful, terrible, horrible, afraid)
3
startling
10 years ago|22k views|share |citing 
APASmart Define. (2016). frightful thesaurus. Retrieved September 25, 2026, from https://smartdefine.org/frightful/thesaurus/synonyms
ChicagoSmart Define. 2016. "frightful thesaurus" https://smartdefine.org/frightful/thesaurus/synonyms (accessed September 25, 2026).
HarvardSmart Define 2016, frightful thesaurus, Smart Define, viewed 25 September, 2026, <https://smartdefine.org/frightful/thesaurus/synonyms>.
MLASmart Define. "frightful thesaurus" 29 March 2016. Web. 25 September 2026. <https://smartdefine.org/frightful/thesaurus/synonyms>