The Collaborative International Dictionary of English v.0.48:

Allocution \Al`lo*cu"tion\, n. [L. allocuto, fr. alloqui to
   speak to; ad + loqui to speak: cf. F. allocution.]
   1. The act or manner of speaking to, or of addressing in
      words.
      [1913 Webster]

   2. An address; a hortatory or authoritative address as of a
      pope to his clergy. --Addison.
      [1913 Webster]

WordNet (r) 3.0 (2006):

allocution
    n 1: (rhetoric) a formal or authoritative address that advises
         or exhorts