The Collaborative International Dictionary of English v.0.48:

Spy \Spy\ (sp[imac]), v. t. [imp. & p. p. Spied (sp[imac]d);
   p. pr. & vb. n. Spying.] [OE. spien, espien, OF. espier, F.
   ['e]pier, OHG. speh[=o]n, G. sp[aum]hen; akin to L. specere
   to see, Skr. spa[,c]. [root] 169. Cf. Espy, v. t.,
   Aspect, Auspice, Circumspect, Conspicuous, Despise,
   Frontispiece, Inspect, Prospect, Respite, Scope,
   Specimen, Spectacle, Specter, Speculate, Spice,
   Spite, Suspicion.]
   1. To gain sight of; to discover at a distance, or in a state
      of concealment; to espy; to see.
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            One, in reading, skipped over all sentences where he
            spied a note of admiration.           --Swift.
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   2. To discover by close search or examination.
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            Look about with your eyes; spy what things are to be
            reformed in the church of England.    --Latimer.
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   3. To explore; to view, inspect, and examine secretly, as a
      country; -- usually with out.
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            Moses sent to spy out Jaazer, and they took the
            villages thereof.                     --Num. xxi.
                                                  32.
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The Collaborative International Dictionary of English v.0.48:

Spied \Spied\,
   imp. & p. p. of Spy.
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