3
evil(adjective, black, baleful, bodeful)
3
evil-boding(adjective, awful, fear, black, horror)
3
evil boding(adjective, awful, fear, black, horror)
3
fantastic
3
fearful
3
formidable(adjective, fear)
3
grim(adjective, black, baleful, bodeful)
3
horrible
3
ill
3
ill-starred
3
ill boding(adjective, awful, fear, black, horror)
3
ill omened(adjective, awful, fear, black, horror)
3
inspiring(adjective, great, excellent, superb, super)
3
lowering
3
lurid(adjective, awful, fear, black, horror)
3
minatory(adjective, threatening)
3
pivotal
3
presageful(adjective, awful, fear, black, horror)
3
sinistrous(adjective, awful, fear, black, horror)
3
sullen(adjective, awful, fear, black, horror)
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APASmart Define. (2015). portentous thesaurus. Retrieved September 28, 2026, from https://smartdefine.org/portentous/thesaurus/synonyms
ChicagoSmart Define. 2015. "portentous thesaurus" https://smartdefine.org/portentous/thesaurus/synonyms (accessed September 28, 2026).
HarvardSmart Define 2015, portentous thesaurus, Smart Define, viewed 28 September, 2026, <https://smartdefine.org/portentous/thesaurus/synonyms>.
MLASmart Define. "portentous thesaurus" 10 April 2015. Web. 28 September 2026. <https://smartdefine.org/portentous/thesaurus/synonyms>