es·pi·o·nage (ĕspē-ə-näzh′, -nĭj)
The practice of spying or of using spies to obtain secret information, especially regarding a government or business.
[French espionnage, from espionner, to spy, from Old French espion, spy, from Old Italian spione, of Germanic origin; see spek- in the Appendix of Indo-European roots.]
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.