ghost vs spook

ghost and spook both are nouns.

Word	Noun	Adjective	Verb	Adverb
ghost	Yes	No	Yes	No
spook	Yes	No	Yes	No

As nouns, ghost and spook are synonyms defined as:

Other synonyms of ghost include shade, specter, spectre, wraith.

ghost (noun)	spook (noun)
a mental representation of some haunting experience	a mental representation of some haunting experience
a suggestion of some quality	someone unpleasantly strange or eccentric
the visible disembodied soul of a dead person
a writer who gives the credit of authorship to someone else

ghost (verb)	spook (verb)
write for someone else	frighten or scare, and often provoke into a violent action
haunt like a ghost; pursue
move like a ghost