The Collaborative International Dictionary of English v.0.48:
Vade mecum \Va`de me"cum\ [L., go with me.] A book or other thing that a person carries with him as a constant companion; a manual; a handbook. [1913 Webster]WordNet (r) 3.0 (2006):
vade mecum n 1: a concise reference book providing specific information about a subject or location [syn: handbook, enchiridion, vade mecum]