[1] : The Collaborative International Dictionary of English v.0.48

spy \spy\, v. i.
   to search narrowly; to scrutinize.
   1913 webster

         it is my nature's plague
         to spy into abuses.                      --shak.
   1913 webster

[2] : The Collaborative International Dictionary of English v.0.48

spy \spy\, n.; pl. spies spimacz. see spy, v., and cf.
   espy, n.
   1. one who keeps a constant watch of the conduct of others.
      "these wretched spies of wit." --dryden.
      1913 webster

   2. mil. a person sent secretly into an enemy's camp,
      territory, or fortifications, to inspect his works,
      ascertain his strength, movements, or designs, and to
      communicate such intelligence to the proper officer.
      1913 webster

   spy money, money paid to a spy; the reward for private or
      secret intelligence regarding the enemy.

   spy wednesday eccl., the wednesday immediately preceding
      the festival of easter; -- so called in allusion to the
      betrayal of christ by judas iscariot.
      1913 webster

   syn: see emissary, and scout.
        1913 webster
see also:
spies spy espy spy money spy wednesday emissary 
scout 

[3] : The Collaborative International Dictionary of English v.0.48

spy \spy\ spimac, v. t. imp.  p. p. spied spimacd;
   p. pr.  vb. n. spying. oe. spien, espien, of. espier, f.
   'epier, ohg. speh=on, g. spaumhen; 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.
      1913 webster

            one, in reading, skipped over all sentences where he
            spied a note of admiration.           --swift.
      1913 webster

   2. to discover by close search or examination.
      1913 webster

            look about with your eyes; spy what things are to be
            reformed in the church of england.    --latimer.
      1913 webster

   3. to explore; to view, inspect, and examine secretly, as a
      country; -- usually with out.
      1913 webster

            moses sent to spy out jaazer, and they took the
            villages thereof.                     --num. xxi.
                                                  32.
      1913 webster
see also:
spied spying espy aspect auspice circumspect 
conspicuous despise frontispiece inspect prospect 
respite scope specimen spectacle specter 
speculate spice spite suspicion 

[4] : WordNet (r) 2.0

spy
     n 1: military a secret agent hired by a state to obtain
          information about its enemies or by a business to obtain
          industrial secrets from competitors syn: undercover
          agent
     2: a secret watcher; someone who secretly watches other people;
        "my spies tell me that you had a good time last night"
     v 1: catch sight of syn: descry, spot, espy
     2: watch, observe, or inquire secretly syn: stag, snoop, sleuth
     3: secretly collect sensitive or classified information; engage
        in espionage; "spy for the russians"
     also: spied
see also:
undercover agent descry spot espy stag snoop 
sleuth spied 

[5] : Moby Thesaurus II by Grady Ward, 1.0

114 moby thesaurus words for "spy":
   cia man, agent, be vigilant, be watchful, beagle, behold, betrayer,
   blab, blabber, blabberer, blabbermouth, bug, case, catch sight of,
   clap eyes on, cloak-and-dagger operative,
   counterintelligence agent, counterspy, delator, descry, detect,
   detective, dig out, discern, discover, distinguish, double agent,
   espionage agent, espy, eye, eyeball, ferret out, fink, fish out,
   follow, gaze at, glimpse, grub up, have a looksee, have in sight,
   hold in view, hunt out, identify, informer, inside man,
   intelligence agent, investigator, keep in sight, keep in view,
   keep under observation, ken, lay eyes on, look after, look at,
   look on, look upon, make a reconnaissance, make out, meddle,
   military-intelligence man, narc, naval-intelligence man, nose,
   notice, observe, operative, peacher, peek, peep, perceive,
   pick out, pick up, play the spy, pry, pry out,
   put under surveillance, recognize, reconnoiter, reconnoiterer,
   regard, root out, scout, scout out, search out, secret agent, see,
   sense, sight, sleuth, snitch, snitcher, snoop, spook, spot,
   spotter, spy out, spy upon, spy-catcher, squealer, stag, stake out,
   stool pigeon, stoolie, take in, talebearer, tattler, tattletale,
   telltale, twig, undercover man, view, watch, whistle-blower,
   witness

Spy >> S Words
Spy, definition of term: Spy
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