The Collaborative International Dictionary of English v.0.48:

Perjure \Per"jure\, v. t. [imp. & p. p. Perjured; p. pr. & vb.
   n. Perjuring.] [F. parjurer, L. perjurare, perjerare; per
   through, over + jurare to swear. See Jury.]
   1. To cause to violate an oath or a vow; to cause to make
      oath knowingly to what is untrue; to make guilty of
      perjury; to forswear; to corrupt; -- often used
      reflexively; as, he perjured himself.
      [1913 Webster]

            Want will perjure
            The ne'er-touched vestal.             --Shak.
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   2. To make a false oath to; to deceive by oaths and
      protestations. [Obs.]
      [1913 Webster]

            And with a virgin innocence did pray
            For me, that perjured her.            --J. Fletcher.
      [1913 Webster]

   Syn: To Perjure, Forswear.

   Usage: These words have been used interchangeably; but there
          is a tendency to restrict perjure to that species of
          forswearing which constitutes the crime of perjury at
          law, namely, the willful violation of an oath
          administered by a magistrate or according to law.
          [1913 Webster]