Princeton's WordNet

1. barbarous, brutal, cruel, fell, roughshod, savage, vicious(adj)

   (of persons or their actions) able or disposed to inflict pain or suffering

   "a barbarous crime"; "brutal beatings"; "cruel tortures"; "Stalin's roughshod treatment of the kulaks"; "a savage slap"; "vicious kicks"

2. evil, vicious(adj)

   having the nature of vice

3. condemnable, criminal, deplorable, reprehensible, vicious(adj)

   bringing or deserving severe rebuke or censure

   "a criminal waste of talent"; "a deplorable act of violence"; "adultery is as reprehensible for a husband as for a wife"

4. poisonous, venomous, vicious(adj)

   marked by deep ill will; deliberately harmful

   "poisonous hate"; "venomous criticism"; "vicious gossip"

Kernerman English Learner's Dictionary

1. vicious(adjective)ˈvɪʃ əs

   ≠ gentle

   a vicious attack; a breed of dog that can be vicious

2. viciousˈvɪʃ əs

   unkind and causing harm

   vicious comments; a vicious rumor; He was viciously attacked by two masked men.; Her opponent criticized her viciously.

Wiktionary

1. vicious(Adjective)

   Pertaining to vice; characterised by immorality or depravity.

2. vicious(Adjective)

   Evil, immoral or depraved.

3. vicious(Adjective)

   Violent, destructive and cruel.

4. vicious(Adjective)

   Savage and aggressive.

Origin: From vicious, vicious (modern French vicieux), from vitiosus, from vitium.

Webster Dictionary

1. Vicious(adj)

   characterized by vice or defects; defective; faulty; imperfect

2. Vicious(adj)

   addicted to vice; corrupt in principles or conduct; depraved; wicked; as, vicious children; vicious examples; vicious conduct

3. Vicious(adj)

   wanting purity; foul; bad; noxious; as, vicious air, water, etc

4. Vicious(adj)

   not correct or pure; corrupt; as, vicious language; vicious idioms

5. Vicious(adj)

   not well tamed or broken; given to bad tricks; unruly; refractory; as, a vicious horse

6. Vicious(adj)

   bitter; spiteful; malignant

The Roycroft Dictionary

1. vicious

   1. To be natural. 2. To give up lying. (A word taken from the Zynrxi, and first used by the French at the Siege of Paris to describe the Germans; hence, any one who does anything impolite or acts in any way strictly in accordance with his innate tastes.)

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