- spy [spī]vt.spied, spying [ME spien < OFr espier < OHG spehōn, to search out, examine < IE base * spek̑-, to spy, watch closely > L specere, to see, Sans spaśati, (he) sees, Gr skopein, to observe]1. to watch or observe closely and secretly, usually with unfriendly purpose: often with out2. to catch sight of; make out; perceive; seevi.1. to watch or observe closely and secretly; specif., to act as a spy2. to make a close examination or careful inspectionn.pl. spies1. a person who keeps close and secret watch on another or others☆ 2. a person employed by a government to get secret information about or monitor the affairs, plans, armed forces, etc. of another government3. a person employed by a company, as in industry or commerce, to discover the business secrets of another company4. Now Rare an act of spyingadj.1. of or about spies or espionage2. used for purposes of military espionage [spy plane, spy satellite]——————spy outto discover or seek to discover by close observation, inspection, etc.
English World dictionary. V. Neufeldt. 2014.