7
challenging(adjective, importance, valuable, main, notable)
7
constitutive(adjective, importance, valuable, main, notable)
7
disastrous(adjective, awful, fear, black, horror)
7
donnish(adjective, importance, valuable, main, notable)
7
essential(adjective, importance, valuable, main, notable)
7
far reaching(adjective, importance, valuable, main, notable)
7
grandiloquent
7
great(adjective, importance, valuable, main, notable)
7
high-up(adjective, importance, valuable, main, notable)
7
ill-fated(adjective, exciting, foreboding, ominous)
7
ill-omened(adjective, awful, fear, black, horror)
7
influential(adjective, importance, valuable, main, notable)
7
key(adjective, importance, valuable, main, notable)
7
key-note(adjective, importance, valuable, main, notable)
7
newsworthy(adjective, importance, valuable, main, notable)
7
outstanding(adjective, importance, valuable, main, notable)
7
pretentious(adjective, importance, main, extremely significant)
7
prophetic(adjective, exciting, foreboding, ominous)
7
purposeful(adjective, importance, valuable, main, notable)
7
responsible(adjective, importance, valuable, main, notable)
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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>