The Collaborative International Dictionary of English v.0.48:

pain \pain\ (p[=a]n), n. [OE. peine, F. peine, fr. L. poena,
   penalty, punishment, torment, pain; akin to Gr. poinh`
   penalty. Cf. Penal, Pine to languish, Punish.]
   1. Punishment suffered or denounced; suffering or evil
      inflicted as a punishment for crime, or connected with the
      commission of a crime; penalty. --Chaucer.
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            We will, by way of mulct or pain, lay it upon him.
                                                  --Bacon.
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            Interpose, on pain of my displeasure. --Dryden.
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            None shall presume to fly, under pain of death.
                                                  --Addison.
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   2. Any uneasy sensation in animal bodies, from slight
      uneasiness to extreme distress or torture, proceeding from
      a derangement of functions, disease, or injury by
      violence; bodily distress; bodily suffering; an ache; a
      smart. "The pain of Jesus Christ." --Chaucer.
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   Note: Pain may occur in any part of the body where sensory
         nerves are distributed, and it is always due to some
         kind of stimulation of them. The sensation is generally
         interpreted as originating at the peripheral end of the
         nerve.
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   3. pl. Specifically, the throes or travail of childbirth.
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            She bowed herself and travailed, for her pains came
            upon her.                             --1 Sam. iv.
                                                  19.
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   4. Uneasiness of mind; mental distress; disquietude; anxiety;
      grief; solicitude; anguish. Also called mental pain.
      --Chaucer.
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            In rapture as in pain.                --Keble.
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   5. See Pains, labor, effort.
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   Bill of pains and penalties. See under Bill.

   To die in the pain, to be tortured to death. [Obs.]
      --Chaucer.
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