4
negative(adjective, injurious, unfavorable, disparaging, hurtful)
4
objectionable(adjective, bad, offensive, rude, unpleasant)
4
offensive(adjective, bad, severe, evil, awful)
4
perilous(adjective, risky, dangerous, injurious, unsafe)
4
pestilent(adjective, unhealthy, dangerous, fatal, unwholesome)
4
pestilential(adjective, injurious, damaging, deadly, destructive)
4
polluted(adjective, bad, offensive, foul, revolting)
4
severe(adjective, bad, offensive, awful, terrible)
4
sinful(adjective, corrupt, immoral, injurious, damaging)
4
threatening(adjective, risky, dangerous, menacing, unsafe)
4
unfortunate
4
unhelpful(adjective, unpleasant, damaging, hurtful, detrimental)
4
unhygienic(adjective, injurious, detrimental)
4
unsanitary(injurious, detrimental)
4
useless(adjective, worthless, second-rate, arouse bad emotions, crummy)
4
violent
4
wounding(adjective, awful, terrible, cruel, unkind)
3
mean(adjective, person, harsh, cruel, hostile)
3
terrible(adjective, dangerous)
3
alarming(adjective, dangerous, arouse bad emotions)
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APASmart Define. (2016). harmful thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/harmful/thesaurus/synonyms
ChicagoSmart Define. 2016. "harmful thesaurus" https://smartdefine.org/harmful/thesaurus/synonyms (accessed September 24, 2026).
HarvardSmart Define 2016, harmful thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/harmful/thesaurus/synonyms>.
MLASmart Define. "harmful thesaurus" 24 March 2016. Web. 24 September 2026. <https://smartdefine.org/harmful/thesaurus/synonyms>