spook

Noun

• a mental representation of some haunting experience
  • he looked like he had seen a ghost
    
  • it aroused specters from his past
    

• someone unpleasantly strange or eccentric

Verb

• frighten or scare, and often provoke into a violent action
  • The noise spooked the horse
    

Related words

• Synonyms: 
  ghost , shade , wraith , specter , spectre , creep , weirdo , weirdie , weirdy