1. [n]  an army unit usually consisting of two or more divisions
2. [n]  a body of people associated together; "diplomatic corps"

Corps
Book Four in the continuing saga of The Corps, from the author of Counterattack which became an immediate national bestseller in hardcover. The Corps combines the best elements of military history and the war story , wrote Publishers Weekly, the telling detail and political tangle of one mated to the energy and sweep of the other . Here is a story of one of the bloodiest conflicts of the Pacific, the epic struggle for Guadalcanal.

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1. \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.
            By what craft in my corps, it cometh [commences] and
            where.                                --Piers
                                                  Plowman.
   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.
            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. )
   3. A body or code of laws. [Obs.]
            The whole corps of the law.           --Bacon.
   4. (Eccl.) The land with which a prebend or other
      ecclesiastical office is endowed. [Obs.]
            The prebendaries over and above their reserved rents
            have a corps.                         --Bacon.
   {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.
   

2. \Corps\, n. [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.