The Collaborative International Dictionary of English v.0.48:

Laudator \Lau*da"tor\, n. [L.]
   1. One who lauds.
      [1913 Webster]

   2. (Law) An arbitrator. [Obs.] --Cowell.
      [1913 Webster]

WordNet (r) 3.0 (2006):

laudator
    n 1: someone who communicates high praise [syn: laudator,
         lauder, extoller]