Definition of "vade mecum" []

• A useful thing that one constantly carries about. (noun)
• A book, such as a guidebook, for ready reference. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Their teachings and monitions have been the political vade mecum of my life."
• "William Dean Howells devoted two long reviews to it, and overnight the book became the vade mecum of the intelligentsia of the day: as an eminent sociologist told Veblen, “It fluttered the dovecotes of the East.”"