The Collaborative International Dictionary of English v.0.48:

Prescribe \Pre*scribe"\, v. i.
   1. To give directions; to dictate.
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            A forwardness to prescribe to their opinions.
                                                  --Locke.
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   2. To influence by long use [Obs.] --Sir T. Browne.
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   3. (Med.) To write or to give medical directions; to indicate
      remedies; as, to prescribe for a patient in a fever.
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   4. (Law) To claim by prescription; to claim a title to a
      thing on the ground of immemorial use and enjoyment, that
      is, by a custom having the force of law.
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The Collaborative International Dictionary of English v.0.48:

Prescribe \Pre*scribe"\, v. t. [imp. & p. p. Prescribed; p. pr
   & vb. n. Prescribing.] [L. praescribere, praescriptum; prae
   before + scriebe to write. See Scribe.]
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   1. To lay down authoritatively as a guide, direction, or rule
      of action; to impose as a peremptory order; to dictate; to
      appoint; to direct.
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            Prescribe not us our duties.          --Shak.
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            Let streams prescribe their fountains where to run.
                                                  --Dryden.
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   2. (Med.) To direct, as a remedy to be used by a patient; as,
      the doctor prescribed quinine.
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   Syn: To appoint; order; command; dictate; ordain; institute;
        establish.
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WordNet (r) 3.0 (2006):

prescribe
    v 1: issue commands or orders for [syn: order, prescribe,
         dictate]