The Collaborative International Dictionary of English v.0.48:

Sense \Sense\, n. [L. sensus, from sentire, sensum, to perceive,
   to feel, from the same root as E. send; cf. OHG. sin sense,
   mind, sinnan to go, to journey, G. sinnen to meditate, to
   think: cf. F. sens. For the change of meaning cf. See, v.
   t. See Send, and cf. Assent, Consent, Scent, v. t.,
   Sentence, Sentient.]
   1. (Physiol.) A faculty, possessed by animals, of perceiving
      external objects by means of impressions made upon certain
      organs (sensory or sense organs) of the body, or of
      perceiving changes in the condition of the body; as, the
      senses of sight, smell, hearing, taste, and touch. See
      Muscular sense, under Muscular, and Temperature
      sense, under Temperature.
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            Let fancy still my sense in Lethe steep. --Shak.
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            What surmounts the reach
            Of human sense I shall delineate.     --Milton.
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            The traitor Sense recalls
            The soaring soul from rest.           --Keble.
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   2. Perception by the sensory organs of the body; sensation;
      sensibility; feeling.
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            In a living creature, though never so great, the
            sense and the affects of any one part of the body
            instantly make a transcursion through the whole.
                                                  --Bacon.
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   3. Perception through the intellect; apprehension;
      recognition; understanding; discernment; appreciation.
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            This Basilius, having the quick sense of a lover.
                                                  --Sir P.
                                                  Sidney.
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            High disdain from sense of injured merit. --Milton.
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   4. Sound perception and reasoning; correct judgment; good
      mental capacity; understanding; also, that which is sound,
      true, or reasonable; rational meaning. "He speaks sense."
      --Shak.
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            He raves; his words are loose
            As heaps of sand, and scattering wide from sense.
                                                  --Dryden.
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   5. That which is felt or is held as a sentiment, view, or
      opinion; judgment; notion; opinion.
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            I speak my private but impartial sense
            With freedom.                         --Roscommon.
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            The municipal council of the city had ceased to
            speak the sense of the citizens.      --Macaulay.
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   6. Meaning; import; signification; as, the true sense of
      words or phrases; the sense of a remark.
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            So they read in the book in the law of God
            distinctly, and gave the sense.       --Neh. viii.
                                                  8.
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            I think 't was in another sense.      --Shak.
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   7. Moral perception or appreciation.
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            Some are so hardened in wickedness as to have no
            sense of the most friendly offices.   --L' Estrange.
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   8. (Geom.) One of two opposite directions in which a line,
      surface, or volume, may be supposed to be described by the
      motion of a point, line, or surface.
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   Common sense, according to Sir W. Hamilton:
      (a) "The complement of those cognitions or convictions
          which we receive from nature, which all men possess in
          common, and by which they test the truth of knowledge
          and the morality of actions."
      (b) "The faculty of first principles." These two are the
          philosophical significations.
      (c) "Such ordinary complement of intelligence, that,if a
          person be deficient therein, he is accounted mad or
          foolish."
      (d) When the substantive is emphasized: "Native practical
          intelligence, natural prudence, mother wit, tact in
          behavior, acuteness in the observation of character,
          in contrast to habits of acquired learning or of
          speculation."

   Moral sense. See under Moral,
      (a) .

   The inner sense, or The internal sense, capacity of the
      mind to be aware of its own states; consciousness;
      reflection. "This source of ideas every man has wholly in
      himself, and though it be not sense, as having nothing to
      do with external objects, yet it is very like it, and
      might properly enough be called internal sense." --Locke.

   Sense capsule (Anat.), one of the cartilaginous or bony
      cavities which inclose, more or less completely, the
      organs of smell, sight, and hearing.

   Sense organ (Physiol.), a specially irritable mechanism by
      which some one natural force or form of energy is enabled
      to excite sensory nerves; as the eye, ear, an end bulb or
      tactile corpuscle, etc.

   Sense organule (Anat.), one of the modified epithelial
      cells in or near which the fibers of the sensory nerves
      terminate.
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   Syn: Understanding; reason.

   Usage: Sense, Understanding, Reason. Some philosophers
          have given a technical signification to these terms,
          which may here be stated. Sense is the mind's acting
          in the direct cognition either of material objects or
          of its own mental states. In the first case it is
          called the outer, in the second the inner, sense.
          Understanding is the logical faculty, i. e., the power
          of apprehending under general conceptions, or the
          power of classifying, arranging, and making
          deductions. Reason is the power of apprehending those
          first or fundamental truths or principles which are
          the conditions of all real and scientific knowledge,
          and which control the mind in all its processes of
          investigation and deduction. These distinctions are
          given, not as established, but simply because they
          often occur in writers of the present day.
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WordNet (r) 3.0 (2006):

sense organ
    n 1: an organ having nerve endings (in the skin or viscera or
         eye or ear or nose or mouth) that respond to stimulation
         [syn: sense organ, sensory receptor, receptor] [ant:
         effector]