The Collaborative International Dictionary of English v.0.48:

Investiture \In*ves"ti*ture\ (?; 135), n. [LL. investitura: cf.
   F. investiture.]
   [1913 Webster]
   1. The act or ceremony of investing, or the state of being
      invested, as with an office; a giving possession; also,
      the right of so investing.
      [1913 Webster]

            He had refused to yield up to the pope the
            investiture of bishops.               --Sir W.
                                                  Raleigh.
      [1913 Webster]

   2. (Feudal Law) Livery of seizin.
      [1913 Webster]

            The grant of land or a feud was perfected by the
            ceremony of corporal investiture, or open delivery
            of possession.                        --Blackstone.
      [1913 Webster]

   3. That with which anyone is invested or clothed; investment;
      clothing; covering.
      [1913 Webster]

            While we yet have on
            Our gross investiture of mortal weeds. --Trench.
      [1913 Webster]

WordNet (r) 3.0 (2006):

investiture
    n 1: the ceremony of installing a new monarch [syn:
         coronation, enthronement, enthronization,
         enthronisation, investiture]
    2: the ceremonial act of clothing someone in the insignia of an
       office; the formal promotion of a person to an office or rank
       [syn: investment, investiture]