6
sulphurous
6
unfriendly(adjective, mean, nasty, hostile, bitter)
6
unhealthy(adjective, harmful, injurious, damaging, noxious)
6
vindictive(adjective, nasty, wicked, hostile, bitter)
5
astringent
5
damaging(adjective, harmful, injurious, destructive, detrimental)
5
dangerous(adjective, wicked, rotten, harmful, fatal)
5
despiteful(adjective, mean, nasty, hateful, spiteful)
5
detrimental(adjective, mean, bad, evil, nasty)
5
distressing(adjective, wicked)
5
embittered(adjective, hard, love, severe, nasty)
5
intense(adjective, severe, nasty, wicked, hostile)
5
mean(adjective, nasty, wicked, unfriendly, hateful)
5
pestilent(adjective, help, unhealthy, deadly, fatal)
5
pestilential(adjective, help, unhealthy, deadly, noxious)
5
poignant(adjective, evil, nasty, harsh, vicious)
5
poison(adjective, help, poisonous, lethal)
5
splenetic(adjective, hostile)
5
sullen(adjective, severe, nasty, hostile, resentful)
4
acidulous
11 years ago|14k views|share |citing 
APASmart Define. (2015). virulent thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/virulent/thesaurus/synonyms
ChicagoSmart Define. 2015. "virulent thesaurus" https://smartdefine.org/virulent/thesaurus/synonyms (accessed September 24, 2026).
HarvardSmart Define 2015, virulent thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/virulent/thesaurus/synonyms>.
MLASmart Define. "virulent thesaurus" 3 August 2015. Web. 24 September 2026. <https://smartdefine.org/virulent/thesaurus/synonyms>