11
unwholesome(adjective, offensive, foul, unhealthy, harmful)
10
ill(adjective, help, bad, evil, contrary)
10
disastrous(adjective, adverse, harmful, injurious, damaging)
10
poisonous(adjective, mean, bad, nasty, offensive)
9
deadly(adjective, bad, evil, cruel, unkind)
9
malign(adjective, mean, bad, evil, nasty)
9
negative(adjective, bad, unfriendly, antagonistic, harmful)
9
ruinous(adjective, mean, bad, wrong, evil)
9
toxic(adjective, bad, evil, offensive, foul)
8
noisome(adjective, bad, evil, harmful, injurious)
7
catastrophic(adjective, adverse, harmful, injurious, damaging)
7
dangerous(adjective, bad, cruel, unkind, distressing)
7
grave(adjective, importance, main, dangerous, extremely significant)
7
lethal(adjective, bad, evil, harmful, dangerous)
7
nocuous(adjective, cruel, negative, unkind, harmful)
7
not good
7
serious(adjective, importance, main, dangerous, extremely significant)
6
suicidal(adjective, harmful, injurious, damaging, deadly)
6
venomous(adjective, mean, bad, evil, nasty)
5
foul(adjective, evil, offensive, unhealthy, harmful)
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APASmart Define. (2016). detrimental thesaurus. Retrieved October 1, 2026, from https://smartdefine.org/detrimental/thesaurus/synonyms
ChicagoSmart Define. 2016. "detrimental thesaurus" https://smartdefine.org/detrimental/thesaurus/synonyms (accessed October 1, 2026).
HarvardSmart Define 2016, detrimental thesaurus, Smart Define, viewed 1 October, 2026, <https://smartdefine.org/detrimental/thesaurus/synonyms>.
MLASmart Define. "detrimental thesaurus" 24 March 2016. Web. 1 October 2026. <https://smartdefine.org/detrimental/thesaurus/synonyms>