order book vs order paper

order book and order paper both are nouns.

Word	Noun	Adjective	Verb	Adverb
order book	Yes	No	No	No
order paper	Yes	No	No	No

As nouns, order book and order paper are synonyms defined as:

order book (noun)	order paper (noun)
a book in which customers' orders are entered; usually makes multiple copies of the order	a printed copy of the order of the day
a printed copy of the order of the day