Source : Webster's Revised Unabridged Dictionary (1913)

Interpellation \In`ter*pel*la"tion\, n. [L. interpellatio: cf.
   F. interpellation.]
   1. The act of interpelling or interrupting; interruption.
      ``Continual interpellations.'' --Bp. Hall.

   2. The act of interposing or interceding; intercession.

            Accepted by his interpellation and intercession.
                                                  --Jer. Taylor.

   3. An act of interpellating, or of demanding of an officer an
      explanation of his action; imperative or peremptory
      questioning; a point raised in a debate.

   4. A official summons or citation. --Ayliffe.

Source : WordNet®

interpellation
     n 1: (parliament) a procedure of demanding that a government
          official explain some act or policy
     2: the action of interjecting or interposing an action or
        remark that interrupts [syn: {interjection}, {interposition},
         {interpolation}]