Source : Webster's Revised Unabridged Dictionary (1913)

Veteran \Vet"er*an\, a. [L. veteranus, from vetus, veteris, old;
   akin to Gr. ? year, Skr. vatsara. See {Wether}.]
   Long exercised in anything, especially in military life and
   the duties of a soldier; long practiced or experienced; as, a
   veteran officer or soldier; veteran skill.

         The insinuating eloquence and delicate flattery of
         veteran diplomatists and courtiers.      --Macaulay.

Veteran \Vet"er*an\, n. [L. veteranus (sc. miles): cf. F.
   v['e]t['e]ran.]
   One who has been long exercised in any service or art,
   particularly in war; one who has had.

         Ensigns that pierced the foe's remotest lines, The
         hardy veteran with tears resigns.        --Addison.

   Note: In the United States, during the civil war, soldiers
         who had served through one term of enlistment and had
         re["e]nlisted were specifically designated veterans.

Source : WordNet®

veteran
     adj : rendered competent through trial and experience; "troops
           seasoned in combat"; "a seasoned traveler"; "veteran
           steadiness"; "a veteran officer" [syn: {seasoned}, {veteran(a)}]
     n 1: a serviceman who has seen considerable active service; "the
          veterans laughed at the new recruits" [syn: {veteran
          soldier}]
     2: a person who has served in the armed forces [syn: {vet}, {ex-serviceman}]
     3: an experienced person who has been through many battles;
        someone who has given long service [syn: {old-timer}, {oldtimer},
         {old hand}, {warhorse}, {old stager}, {stager}]