The Collaborative International Dictionary of English v.0.48:

Corps \Corps\ (k[=o]r, pl. k[=o]rz), n. sing. & pl. [F., fr. L.
   corpus body. See Corpse.]
   1. The human body, whether living or dead. [Obs.] See
      Corpse, 1.
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            By what craft in my corps, it cometh [commences] and
            where.                                --Piers
                                                  Plowman.
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   2. A body of men; esp., an organized division of the military
      establishment; as, the marine corps; the corps of
      topographical engineers; specifically, an army corps.
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            A corps operating with an army should consist of
            three divisions of the line, a brigade of artillery,
            and a regiment of cavalry.            --Gen. Upton
                                                  (U. S.
                                                  Tactics. )
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   3. A body or code of laws. [Obs.]
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            The whole corps of the law.           --Bacon.
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   4. (Eccl.) The land with which a prebend or other
      ecclesiastical office is endowed. [Obs.]
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            The prebendaries over and above their reserved rents
            have a corps.                         --Bacon.
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   5. [Ger.] In some countries of Europe, a form of students'
      social society binding the members to strict adherence to
      certain student customs and its code of honor; -- Ger.
      spelling usually korps.
      [Webster 1913 Suppl.]

   Army corps, or (French) Corps d'arm['e]e (k[-o]r`
      d[aum]r`m[asl]"), a body containing two or more divisions
      of a large army, organized as a complete army in itself.


   Corps de logis (k[-o]r` de l[-o]`zh[-e]") [F., body of the
      house], the principal mass of a building, considered apart
      from its wings.

   Corps diplomatique (k?r d?`pl?`m?-t?k") [F., diplomatic
      body], the body of ministers or envoys accredited to a
      government.
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WordNet (r) 3.0 (2006):

corps
    n 1: an army unit usually consisting of two or more divisions
         and their support [syn: corps, army corps]
    2: a body of people associated together; "diplomatic corps"

Moby Thesaurus II by Grady Ward, 1.0:

128 Moby Thesaurus words for "corps":
   Bund, KP, Rochdale cooperative, adjutant general corps, age group,
   air corps, alliance, armored corps, army, army corps, army group,
   army nurse corps, assemblage, association, axis, band, battalion,
   battery, battle group, bevy, bloc, body, brigade, bugle corps,
   bunch, cabal, cadre, cast, chemical corps, clique, coalition,
   cohort, college, column, combat command, combat team, combination,
   combine, common market, company, complement, confederacy,
   confederation, consumer cooperative, contingent, cooperative,
   cooperative society, corps of cadets, corps of signals,
   corps troops, coterie, council, covey, credit union, crew, crowd,
   customs union, dental corps, detachment, detail, division,
   drum corps, economic community, engineer corps, faction,
   federation, field army, field train, file, fleet, flying column,
   free trade area, gang, garrison, group, grouping, groupment,
   in-group, junta, kitchen police, league, legion, machine, maniple,
   marine corps, medical corps, military police corps, mob, movement,
   ordnance corps, organization, out-group, outfit, pack, partnership,
   party, peer group, phalanx, platoon, political machine, posse,
   quartermaster corps, rank, regiment, rifle corps, ring, salon,
   section, set, signal corps, society, squad, squadron, stable,
   string, tactical unit, tank corps, task force, team, train,
   transportation corps, tribe, troop, troupe, union, unit,
   veterinary corps, wing