1. Malicious
2. Malevolent
3. Barbarous
4. Ferocious
5. Savage
6. Brutal
7. Fierce
8. Nasty
9. Cruel
10. Unmerciful
11. Heartless
12. Merciless
13. Oppressive
14. Ruthless
15. Tyrannical
16. Vindictive
17. Inhumane
18. Barbaric
19. Opprobrious
20. Truculent
21. Virulent
22. Vitriolic
23. Atrocious
24. Heinous
25. Monstrous
26. Unrelenting
27. Relentless
28. Sadistic
29. Barbarous
30. Unkind

When looking for synonyms for the word «VICIOUS», there are many options to choose from. Whether you are looking for the best, or simply other words for «VICIOUS», you can find a variety of options to choose from. Some of the best ideas include words such as malicious, malevolent, barbarous, ferocious, savage, brutal, fierce, nasty, cruel, unmerciful, heartless, merciless, oppressive, ruthless, tyrannical, vindictive, inhumane, barbaric, opprobrious, truculent, virulent, vitriolic, atrocious, heinous, monstrous, unrelenting, relentless, sadistic, barbarous, and unkind. Each of these words carries a similar meaning to the word «VICIOUS», and can be used in a variety of contexts.