bookdealer vs book seller

bookdealer and book seller both are nouns.

Word	Noun	Adjective	Verb	Adverb
bookdealer	Yes	No	No	No
book seller	Yes	No	No	No

As nouns, bookdealer and book seller are synonyms defined as:

bookdealer and book seller: a dealer in books; a merchant who sells books

bookdealer (noun)	book seller (noun)
a dealer in books; a merchant who sells books	a dealer in books; a merchant who sells books