Source : Webster's Revised Unabridged Dictionary (1913)

Denounce \De*nounce"\, v. t. [imp. & p. p. {Denounced}; p. pr. &
   vb. n. {Denouncing}.] [F. d['e]noncer, OF. denoncier, fr. L.
   denuntiare, denunciare; de- + nunciare, nuntiare, to
   announce, report, nuntius a messenger, message. See {Nuncio},
   and cf. {Denunciate}.]
   1. To make known in a solemn or official manner; to declare;
      to proclaim (especially an evil). [Obs.]

            Denouncing wrath to come.             --Milton.

            I denounce unto you this day, that ye shall surely
            perish.                               --Deut. xxx.
                                                  18.

   2. To proclaim in a threatening manner; to threaten by some
      outward sign or expression.

            His look denounced desperate.         --Milton.

   3. To point out as deserving of reprehension or punishment,
      etc.; to accuse in a threatening manner; to invoke censure
      upon; to stigmatize.

            Denounced for a heretic.              --Sir T. More.

            To denounce the immoralities of Julius C[ae]sar.
                                                  --Brougham.

Source : WordNet®

denounce
     v 1: speak out against; "He denounced the Nazis"
     2: to accuse or condemn or openly or formally or brand as
        disgraceful; "He denounced the government action"; "She
        was stigmatized by society because she had a child out of
        wedlock" [syn: {stigmatize}, {stigmatise}, {brand}, {mark}]
     3: announce the termination of, as of treaties
     4: give away information about somebody; "He told on his
        classmate who had cheated on the exam" [syn: {tell on}, {betray},
         {give away}, {rat}, {grass}, {shit}, {shop}, {snitch}, {stag}]