1. [n]  children take the roles of doctor or patient or nurse and pretend they are at the doctor's office; "the children explored each other's bodies by playing the game of doctor"
2. [n]  a licensed medical practitioner; "I felt so bad I went to see my doctor"
3. [n]  a person who holds Ph.D. degree from an academic institution; "she is a doctor of philosophy in physics"
4. [n]  a leading theologian in the history of the Roman Catholic Church; "the Doctors of the Church greatly influenced Christian thought down to the late Middle Ages"
5. [v]  give medical treatment to
6. [v]  restore by replacing a part or putting together what is torn or broken; "She repaired her TV set"; "Repair my shoes please"
7. [v]  alter and make impure, as with the intention to deceive; "Sophisticate rose water with geraniol"

Doctor
Explains the educational background, clothing, equipment, and various duties of a doctor.

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1. \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 learned man. [Obs.]
            One of the doctors of Italy, Nicholas Macciavel. --
                                                  Bacon.
   2. An academical title, originally meaning a men 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.
   3. One duly licensed to practice medicine; a member of the
      medical profession; a physician.
            By medicine life may be prolonged, yet death Will
            seize the doctor too.                 -- Shak.
   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}.
   5. (Zo["o]l.) The friar skate. [Prov. Eng.]
   {Doctors' Commons}. See under {Commons}.
   {Doctor's stuff}, physic, medicine. --G. Eliot.
   {Doctor fish} (Zo["o]l.), 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}.
   

2. \Doc"tor\, v. t. [imp. & p. p. {Doctored}; p. pr. & vb.
   n. {Doctoring}.]
   1. To treat as a physician does; to apply remedies to; to
      repair; as, to doctor a sick man or a broken cart.
      [Colloq.]
   2. To confer a doctorate upon; to make a doctor.
   3. To tamper with and arrange for one's own purposes; to
      falsify; to adulterate; as, to doctor election returns; to
      doctor whisky. [Slang]
   

3. \Doc"tor\, v. i.
   To practice physic. [Colloq.]
   

(Luke 2:46; 5:17; Acts 5:34), a teacher. The Jewish doctors taught and disputed in synagogues, or wherever they could find an audience. Their disciples were allowed to propose to them questions. They assumed the office without any appointment to it. The doctors of the law were principally of the sect of the Pharisees. Schools were established after the destruction of Jerusalem at Babylon and Tiberias, in which academical degrees were conferred on those who passed a certain examination. Those of the school of Tiberias were called by the title "rabbi," and those of Babylon by that of "master."