The Collaborative International Dictionary of English v.0.48:

Surgeon \Sur"geon\, n. [OE. surgien, OF. surgien, contr. fr.
   chirurgien. See Chirurgeon.]
   1. One whose profession or occupation is to cure diseases or
      injuries of the body by manual operation; one whose
      occupation is to cure local injuries or disorders (such as
      wounds, dislocations, tumors, etc.), whether by manual
      operation, or by medication and constitutional treatment.
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   2. (Zool.) Any one of numerous species of chaetodont fishes
      of the family Teuthidae, or Acanthuridae, which have
      one or two sharp lancelike spines on each side of the base
      of the tail. Called also surgeon fish, doctor fish,
      lancet fish, and sea surgeon.
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   Surgeon apothecary, one who unites the practice of surgery
      with that of the apothecary. --Dunglison.

   Surgeon dentist, a dental surgeon; a dentist.

   Surgeon fish. See def. 2, above.

   Surgeon general.
      (a) In the United States army, the chief of the medical
          department.
      (b) In the British army, a surgeon ranking next below the
          chief of the medical department.
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The Collaborative International Dictionary of English v.0.48:

doctor \doc"tor\, n. [OF. doctur, L. doctor, teacher, fr. docere
   to teach. See Docile.]
   1. A teacher; one skilled in a profession, or branch of
      knowledge; a learned man. [Obs.]
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            One of the doctors of Italy, Nicholas Macciavel. --
                                                  Bacon.
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   2. An academical title, originally meaning a man so well
      versed in his department as to be qualified to teach it.
      Hence: One who has taken the highest degree conferred by a
      university or college, or has received a diploma of the
      highest degree; as, a doctor of divinity, of law, of
      medicine, of music, or of philosophy. Such diplomas may
      confer an honorary title only.
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   3. One duly licensed to practice medicine; a member of the
      medical profession; a physician.
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            By medicine life may be prolonged, yet death
            Will seize the doctor too.            -- Shak.
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   4. Any mechanical contrivance intended to remedy a difficulty
      or serve some purpose in an exigency; as, the doctor of a
      calico-printing machine, which is a knife to remove
      superfluous coloring matter; the doctor, or auxiliary
      engine, called also donkey engine.
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   5. (Zool.) The friar skate. [Prov. Eng.]
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   Doctors' Commons. See under Commons.

   Doctor's stuff, physic, medicine. --G. Eliot.

   Doctor fish (Zool.), any fish of the genus Acanthurus;
      the surgeon fish; -- so called from a sharp lancetlike
      spine on each side of the tail. Also called barber fish.
      See Surgeon fish.
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