n. A topically organized book of reference on a certain field of knowledge, disregarding the size of it.
the GNU version of the Collaborative International Dictionary of English
n. A book of reference, to be carried in the hand; a manual; a guidebook.
n. A book containing reference information for a specific field.
The Century Dictionary and Cyclopedia
n. A small book or treatise, properly such as may easily be held in the hand; specifically, a manual or compendium, or a guide-book for travellers: as, handbooks of science; a handbook of Italy.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. a concise reference book providing specific information about a subject or location
Word Usage
"The second part of the handbook is about ways to get round filtering (Choosing circumvention, by Nart Villeneuve)."