The Collaborative International Dictionary of English v.0.48:

Prohibit \Pro*hib"it\, v. t. [imp. & p. p. Prohibited; p. pr.
   & vb. n. Prohibiting.] [L. prohibitus, p. p. of prohibere
   to prohibit; pro before, forth + habere to have, hold. See
   Habit.]
   [1913 Webster]
   1. To forbid by authority; to interdict; as, God prohibited
      Adam from eating of the fruit of a certain tree; we
      prohibit a person from doing a thing, and also the doing
      of the thing; as, the law prohibits men from stealing, or
      it prohibits stealing.
      [1913 Webster]

   Note: Prohibit was formerly followed by to with the
         infinitive, but is now commonly followed by from with
         the verbal noun in -ing.
         [1913 Webster]

   2. To hinder; to debar; to prevent; to preclude.
      [1913 Webster]

            Gates of burning adamant,
            Barred over us, prohibit all egress.  --Milton.
      [1913 Webster]

   Syn: To forbid; interdict; debar; prevent; hinder.

   Usage: Prohibit, Forbid. To forbid is Anglo-Saxon, and is
          more familiar; to prohibit is Latin, and is more
          formal or official. A parent forbids his child to be
          out late at night; he prohibits his intercourse with
          the profane and vicious.
          [1913 Webster]