spectre vs spook

spectre and spook both are nouns.

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

As nouns, spectre and spook are synonyms defined as:

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

spectre (noun)	spook (noun)
a mental representation of some haunting experience	a mental representation of some haunting experience
a ghostly appearing figure	someone unpleasantly strange or eccentric

spectre (verb)	spook (verb)
	frighten or scare, and often provoke into a violent action