The Collaborative International Dictionary of English v.0.48:

Purge \Purge\, v. i.
   1. To become pure, as by clarification.
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   2. To have or produce frequent evacuations from the
      intestines, as by means of a cathartic.
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The Collaborative International Dictionary of English v.0.48:

Purge \Purge\, v. t. [imp. & p. p. Purged; p. pr. & vb. n.
   Purging.] [F. purger, L. purgare; purus pure + agere to
   make, to do. See Pure, and Agent.]
   1. To cleanse, clear, or purify by separating and carrying
      off whatever is impure, heterogeneous, foreign, or
      superfluous. "Till fire purge all things new." --Milton.
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   2. (Med.) To operate on as, or by means of, a cathartic
      medicine, or in a similar manner.
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   3. To clarify; to defecate, as liquors.
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   4. To clear of sediment, as a boiler, or of air, as a steam
      pipe, by driving off or permitting escape.
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   5. To clear from guilt, or from moral or ceremonial
      defilement; as, to purge one of guilt or crime.
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            When that he hath purged you from sin. --Chaucer.
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            Purge me with hyssop, and I shall be clean. --Ps.
                                                  li. 7.
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   6. (Law) To clear from accusation, or the charge of a crime
      or misdemeanor, as by oath or in ordeal.
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   7. To remove in cleansing; to deterge; to wash away; -- often
      followed by away.
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            Purge away our sins, for thy name's sake. --Ps.
                                                  lxxix. 9.
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            We 'll join our cares to purge away
            Our country's crimes.                 --Addison.
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The Collaborative International Dictionary of English v.0.48:

Purge \Purge\, n. [Cf. F. purge. See Purge, v. t.]
   1. The act of purging.
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            The preparative for the purge of paganism of the
            kingdom of Northumberland.            --Fuller.
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   2. That which purges; especially, a medicine that evacuates
      the intestines; a cathartic. --Arbuthnot.
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WordNet (r) 3.0 (2006):

purge
    n 1: the act of clearing yourself (or another) from some stigma
         or charge [syn: purge, purging, purgation]
    2: an act of removing by cleansing; ridding of sediment or other
       undesired elements [syn: purge, purging]
    3: an abrupt or sudden removal of a person or group from an
       organization or place; "he died in a purge by Stalin"
    v 1: oust politically; "Deng Xiao Ping was purged several times
         throughout his lifetime" [ant: rehabilitate]
    2: clear of a charge
    3: make pure or free from sin or guilt; "he left the monastery
       purified" [syn: purify, purge, sanctify]
    4: rid of impurities; "purge the water"; "purge your mind"
    5: rinse, clean, or empty with a liquid; "flush the wound with
       antibiotics"; "purge the old gas tank" [syn: flush,
       scour, purge]
    6: eject the contents of the stomach through the mouth; "After
       drinking too much, the students vomited"; "He purged
       continuously"; "The patient regurgitated the food we gave him
       last night" [syn: vomit, vomit up, purge, cast,
       sick, cat, be sick, disgorge, regorge, retch,
       puke, barf, spew, spue, chuck, upchuck, honk,
       regurgitate, throw up] [ant: keep down]
    7: excrete or evacuate (someone's bowels or body); "The doctor
       decided that the patient must be purged"