from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The act or practice of spying or of using spies to obtain secret information, as about another government or a business competitor.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. The act or process of learning secret information through clandestine means.
from the GNU version of the Collaborative International Dictionary of English
- n. The practice or employment of spies; the practice of watching the words and conduct of others, to make discoveries, as spies or secret emissaries; secret watching.
from The Century Dictionary and Cyclopedia
- n. The practice of spying; secret observation of the acts or utterances of another by a spy or emissary; offensive surveillance.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. the systematic use of spies to get military or political secrets
French espionnage, from espionner, to spy, from Old French espion, spy, from Old Italian spione, of Germanic origin; see spek- in Indo-European roots.(American Heritage® Dictionary of the English Language, Fourth Edition)
Recorded since 1793, from French espionnage, from Middle French espionner ("to spy"), from Old French espion ("spy"), itself probably from a Germanic source (akin to Old High German spehon "spy"), possibly via Italian spione (from spia). More at spy (Wiktionary)