evil
adjective /ˈiːvl/,  /ˈiːvɪl/
  /ˈiːvl/
Idioms - (of people) enjoying harming others; morally bad and cruel- Police described the killer as ‘a desperate and evil man’.
- an evil genius/dictator
- President Reagan referred to the Soviet Union as the ‘evil empire’.
- an evil grin
- Her face was full of evil intent.
 Extra ExamplesTopics Personal qualitiesb2- Kristin smiled a particularly evil smile.
- He gave an evil laugh.
- A broad smile hid his evil intentions.
 Oxford Collocations Dictionaryverbs- be
- look
- seem
- …
 - particularly
- really
- truly
- …
 
- having a harmful effect on people; morally bad- evil deeds
- In his speech he described the evil effects of racism.
 
- connected with the devil and with what is bad in the world- It was an ancient charm to ward off evil spirits.
- She had been deceived by an evil demon.
 
- extremely unpleasant- The rubbish bin was giving off an evil smell.
 
Word OriginOld English yfel, of Germanic origin; related to Dutch euvel and German Übel.
Idioms 
the evil hour/day 
- (often humorous) the time when you have to do something difficult or unpleasant- I’d better go and see the dentist—I can’t put off the evil hour any longer.
- If you keep on borrowing, you are only postponing the evil day when you have to pay it all back.
 
somebody’s good/evil genius 
- (especially British English) a person or spirit who is thought to have a good/bad influence over you
a witch’s/an evil brew 
- (British English, informal) an unpleasant drink that is a mixture of different things