vade mecum vs reference book

vade mecum and reference book both are nouns.

Word	Noun	Adjective	Verb	Adverb
vade mecum	Yes	No	No	No
reference book	Yes	No	No	No

As nouns, reference book is a hypernym of vade mecum; that is, reference book is a word with a broader meaning than vade mecum:

vade mecum: a concise reference book providing specific information about a subject or location
reference book: a book to which you can refer for authoritative facts

Other hypernyms of vade mecum include book of facts, reference, reference work.

vade mecum (noun)	reference book (noun)
a concise reference book providing specific information about a subject or location	a book to which you can refer for authoritative facts