noun
1. often capitalized both Bs : a government publication providing information on any topic (as a manual or register of officials) ; especially : a usually detailed government report (as the report of a department or commission)
the United States Department of State issued … a heavily documented 40,000-word Blue Book — F.A.Magruder
2. : a nongovernmental directory or register especially of persons of social prominence
the renowned cast that read like the Blue Book of the London theatre — Brooks Atkinson
3.
a. : a blank blue-covered booklet used in colleges for writing examinations
b. : a college examination