Nouns

(n)creep, weirdo, weirdie, weirdy, spooksomeone unpleasantly strange or eccentric
(n)ghost, shade, spook, wraith, specter, spectrea mental representation of some haunting experience“he looked like he had seen a ghost”, “it aroused specters from his past”

Verbs

(v)spookfrighten or scare, and often provoke into a violent action“The noise spooked the horse”