jacket vs book jacket

jacket and book jacket both are nouns.

Word	Noun	Adjective	Verb	Adverb
jacket	Yes	No	Yes	No
book jacket	Yes	No	No	No

As nouns, book jacket is a hyponym of jacket; that is, book jacket is a word with a more specific, narrower meaning than jacket:

jacket: an outer wrapping or casing
book jacket: a paper jacket for a book; a jacket on which promotional information is usually printed

Other hyponyms of jacket include record jacket, dust cover, dust jacket, dust wrapper.

jacket (noun)	book jacket (noun)
a short coat	a paper jacket for a book; a jacket on which promotional information is usually printed
an outer wrapping or casing
(dentistry) dental appliance consisting of an artificial crown for a broken or decayed tooth
the tough metal shell casing for certain kinds of ammunition
the outer skin of a potato

jacket (verb)	book jacket (verb)
put a jacket on
provide with a thermally non-conducting cover