The Collaborative International Dictionary of English v.0.48:

Punishment \Pun"ish*ment\, n.
   1. The act of punishing.
      [1913 Webster]

   2. Any pain, suffering, or loss inflicted on a person because
      of a crime or offense.
      [1913 Webster]

            I never gave them condign punishment. --Shak.
      [1913 Webster]

            The rewards and punishments of another life.
                                                  --Locke.
      [1913 Webster]

   3. (Law) A penalty inflicted by a court of justice on a
      convicted offender as a just retribution, and incidentally
      for the purposes of reformation and prevention.
      [1913 Webster]

   4. Severe, rough, or disastrous treatment. [Colloq. or Slang]
      [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

punishment
    n 1: the act of punishing [syn: punishment, penalty,
         penalization, penalisation]

Moby Thesaurus II by Grady Ward, 1.0:

70 Moby Thesaurus words for "punishment":
   abuse, admonishment, admonition, amercement, avengement,
   banishment, battering, beating, caning, cashiering, castigating,
   castigation, chastening, chastisement, chastising, comeuppance,
   compensation, correction, criticism, damage, desert, deserts,
   discipline, disciplining, dressing-down, electrocution,
   excommunication, execution, exile, fine, flogging, hanging, harm,
   imprisonment, incarceration, injury, just deserts, lashing,
   maltreatment, mauling, mulct, paddling, penal retribution,
   penalization, penalty, penance, price, punition, quittance, rebuke,
   recompense, reprisal, reproof, requital, retribution, revenge,
   reward, rod, scolding, scourging, sentence, sentencing, spanking,
   thrashing, torture, trouncing, what for, what is due,
   what is merited, whipping



Easton's 1897 Bible Dictionary:

Punishment
   The New Testament lays down the general principles of good
   government, but contains no code of laws for the punishment of
   offenders. Punishment proceeds on the principle that there is an
   eternal distinction between right and wrong, and that this
   distinction must be maintained for its own sake. It is not
   primarily intended for the reformation of criminals, nor for the
   purpose of deterring others from sin. These results may be
   gained, but crime in itself demands punishment. (See MURDER
   ¯T0002621; THEFT.)

     Endless, of the impenitent and unbelieving. The rejection of
   this doctrine "cuts the ground from under the gospel...blots out
   the attribute of retributive justice; transmutes sin into
   misfortune instead of guilt; turns all suffering into
   chastisement; converts the piacular work of Christ into moral
   influence...The attempt to retain the evangelical theology in
   connection with it is futile" (Shedd).


Bouvier's Law Dictionary, Revised 6th Ed (1856):

PUNISHMENT, crim. law. Some pain or penalty warranted by law, inflicted on a
person, for the commission of a crime or misdemeanor, or for the omission of
the performance of an act required by law, by the judgment and command of
some lawful court.
     2. The right of society to punish, is derived by Becoaria, Mably, and
some others, from a supposed agreement which the persons who composes the
primitive societies entered into, in order to keep order and, indeed, the
very existence of the state. According to others, it is the interest and
duty of man to live in society; to defend this right, society may exert this
principle in order to support itself, and this it may do, whenever the acts
punishable would endanger the safety of the whole. And Bentham is of opinion
that the foundation of this right is laid in public utility or necessity.
Delinquents are public enemies, and they must be disarmed and prevented from
doing evil, or society must be destroyed. But, if the social compact has
ever existed, says Livingston, its end must have been the preservation of
the natural rights of the members and, therefore the effects of this fiction
are the same with those of the theory which takes abstract justice as the
foundation of the right to punish; for, this justice, if well considered, is
that which assures to each member of the state, the free exercise of his
rights. And if it should be found that utility, the last source from which
the right to punish is derived, is so intimately united to justice that it
is inseparable from it in the practice of law, it will follow that every
system founded on one of these principles must be supported by the others.
     3. To attain their social end, punishments should be exemplary, or
capable of intimidating those who might be tempted to imitate the guilty;
reformatory, or such as should improve the condition of the convicts;
personal, or such as are at least calculated to wound the feelings or affect
the rights of the relations of the guilty divisible, or capable of being
graduated and proportioned to the offence, and the circumstances of each
case; reparable, on account of the fallibility of human justice.
     4. Punishments are either corporal or not corporal. The former are,
death, which is usually denominated capital punishment; imprisonment, which
is either with or without labor; vide Penitentiary; whipping, in some
states, though to the honor of several of them, it is not tolerated in them;
banishment and death.
     5. The punishments which are not corporal, are fines; forfeitures;
suspension or deprivation of some political or civil right deprivation of
office, and being rendered incapable to hold office; compulsion to remove
nuisances.
     6. The object of punishment is to reform the offender; to deter him and
others from committing like offences; and to protect society. Vide 4 Bl.
Com. 7 Rutherf. Inst. B. 1, ch. 18.
     7. Punishment to be just ought to be graduated to the enormity of the
offence. It should never exceed what is requisite to reform the criminal and
to protect society; for whatever goes beyond this, is cruelty and revenge,
the relic of a barbarous age. All the circumstances under which the offender
acted should be considered. Vide Moral Insanity.
     8. The constitution of the United States, amendments, art. 8, forbids
the infliction of "cruel and unusual punishments."
     9. It has been well observed by the author of Principles of Penal Law,
that "when the rights of human nature are not respected, those of the
citizen are gradually disregarded. Those eras are in history found fatal to
liberty, in which cruel punishments predominate. Lenity should be the
guardian of moderate governments; severe penalties, the instruments of
despotism, may give a sudden check to temporary evils, but they have a
tendency to extend themselves to every class of crimes, and their frequency
hardens the sentiments of the people. Une loi rigoureuse produit des crimes.
The excess of the penalty flatters the imagination with the hope of
impunity, and thus becomes an advocate with the offender for the
perpetrating of the offence." Vide Theorie des Lois Criminelles, ch. 2; Bac.
on Crimes and Punishments; Merl. Rep. mot Peine; Dalloz, Dict. mot Peine and
Capital crimes.
    10. Punishments are infamous or not infamous. The former continue
through life, unless the offender has been pardoned, and are not dependent
on the length of time for which the party has been sentenced to suffer
imprisonment; a person convicted of a felony, perjury, and other infamous
crimes cannot, therefore, be a witness nor hold any office, although the
period for which he may have been sentenced to imprisonment, may have
expired by lapse of time. As to the effect of a pardon, vide Pardon.
    11. Those punishments which are not infamous, are such as are inflicted
on persons for misdemeanors, such as assaults and batteries, libels, and the
like. Vide Crimes; Infamy; Penitentiary.