3
unhealthful(adjective, offensive, foul, disgusting, unhealthy)
2
atrocious(adjective, bad, evil, nasty, harsh)
2
badly
2
brutal(adjective, evil, nasty, harsh, vicious)
2
corroding(injurious, damaging, destructive)
2
corrupting(distressing, harmful, injurious, damaging, destructive)
2
crippling(adjective, harmful, injurious, damaging, destructive)
2
cutthroat(adjective, harmful, injurious, damaging, deadly)
2
damnable
2
dead
2
distressing(cruel, unkind, upsetting, harmful, damaging)
2
disturbing(adjective, harmful, threatening, menacing, unfavorable)
2
feral
2
ferocious(adjective, evil, nasty, harsh, vicious)
2
fierce(adjective, evil, nasty, harsh, vicious)
2
menacing(adjective, threatening, injurious, damaging, destructive)
2
miasmatic(adjective, bad, hurtful)
2
repugnant(adjective, bad, offensive, corrupt, foul)
2
repulsive
2
septic
10 years ago|20k views|share |citing 
APASmart Define. (2016). pernicious thesaurus. Retrieved September 25, 2026, from https://smartdefine.org/pernicious/thesaurus/synonyms
ChicagoSmart Define. 2016. "pernicious thesaurus" https://smartdefine.org/pernicious/thesaurus/synonyms (accessed September 25, 2026).
HarvardSmart Define 2016, pernicious thesaurus, Smart Define, viewed 25 September, 2026, <https://smartdefine.org/pernicious/thesaurus/synonyms>.
MLASmart Define. "pernicious thesaurus" 24 March 2016. Web. 25 September 2026. <https://smartdefine.org/pernicious/thesaurus/synonyms>