The Collaborative International Dictionary of English v.0.48:

Compellation \Com`pel*la"tion\, n. [L. compellatio, fr.
   compellare to accost, fr. compellere. See Compel.]
   Style of address or salutation; an appellation. "Metaphorical
   compellations." --Milton.
   [1913 Webster]

         He useth this endearing compellation, "My little
         children."                               --Bp.
                                                  Beveridge.
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         The peculiar compellation of the kings in France is by
         "Sire," which is nothing else but father. --Sir W.
                                                  Temple.
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