5
portentous(adjective, fear, exciting, foreboding)
5
sinister(adjective, hard, severe, offensive, distressing)
5
terrific
5
worrying(adjective, hard, severe, offensive, upsetting)
4
bad(adjective, nasty, delicate, awful, heavy)
4
baleful(adjective, arouse bad emotions)
4
bloodcurdling(adjective, horrible, frightening, horrifying, terrifying)
4
distressing(adjective, hard, severe, offensive, unpleasant)
4
explosive(adjective, untrustworthy, insecure, risky, danger)
4
forbidding(adjective, arouse bad emotions)
4
gruesome
4
hideous(adjective, awful)
4
macabre
4
perilous(adjective, bad, heavy, fear, insecure)
4
ugly
3
agitating(verb, hard, severe, offensive, distressing)
3
brutal(adjective, arouse bad emotions)
3
damaging(adjective, dangerous, arouse bad emotions)
3
destructive(adjective, dangerous, arouse bad emotions)
3
evil(adjective, arouse bad emotions)
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APASmart Define. (2016). alarming thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/alarming/thesaurus/synonyms
ChicagoSmart Define. 2016. "alarming thesaurus" https://smartdefine.org/alarming/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2016, alarming thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/alarming/thesaurus/synonyms>.
MLASmart Define. "alarming thesaurus" 3 April 2016. Web. 20 September 2026. <https://smartdefine.org/alarming/thesaurus/synonyms>