Spy is defined as to secretly watch someone or something.(verb)
An example of to spy is hiding behind a bush and watching someone through their window.
The definition of a spy is a person who secretly watches what people are doing.(noun)
An example of spy is Mata Hari who was employed by Germany during the first world war.
See spy in Webster's New World College Dictionary
Origin: ME spien < OFr espier < OHG spehōn, to search out, examine < IE base *spe-, to spy, watch closely > L specere, to see, Sans spaśati, (he) sees, Gr skopein, to observe
noun pl. spies
See spy in American Heritage Dictionary 4
noun pl. spies spies (spīz)
Origin: Middle English spie
Origin: , from Old French espie
Origin: , from espier, to watch
Origin: , of Germanic origin; see spek- in Indo-European roots.
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