Dictionary:

revenant

  (rĕv'ə-nənt)

1. One that returns after a lengthy absence.
2. One who returns after death.

[French, from present participle of revenir, to return, from Old French. See revenue.]

noun

A supernatural being, such as a ghost: apparition, bogey, bogeyman, bogle, eidolon, ghost, phantasm, phantasma, phantom, shade, shadow, specter, spirit, visitant, wraith. Informal spook. Regional haunt. See beings, supernatural.