Synonyms: fiend, devil, demon, daemon, daimon
Definition: an evil supernatural being
Similar words: evil spirit
Definition: a spirit tending to cause harm
Synonyms: demon
Definition: someone extremely diligent or skillful
Usage: he worked like a demon to finish the job on time; she's a demon at math
Similar words: worker, actor, doer
Definition: a person who acts and gets things done
Usage: he's a principal actor in this affair; when you want something done get a doer; he's a miracle worker
Synonyms: monster, ogre, devil, demon, fiend
Definition: a cruel wicked and inhuman person
Similar words: unpleasant person, disagreeable person
Definition: a person who is not pleasant or agreeable