The Collaborative International Dictionary of English v.0.48:

Preterition \Pre`ter*i"tion\ (?; 277), n. [L. praeteritio: cf.
   F. pr['e]t['e]rition.]
   1. The act of passing, or going past; the state of being
      past. --Bp. Hall.
      [1913 Webster]

   2. (Rhet.) A figure by which, in pretending to pass over
      anything, a summary mention of it is made; as, "I will not
      say, he is valiant, he is learned, he is just." Called
      also paraleipsis.
      [1913 Webster]

   3. (Law) The omission by a testator of some one of his heirs
      who is entitled to a portion. --Bouvier.
      [1913 Webster]

WordNet (r) 3.0 (2006):

preterition
    n 1: suggesting by deliberately concise treatment that much of
         significance is omitted [syn: paralepsis, paraleipsis,
         paralipsis, preterition]

Bouvier's Law Dictionary, Revised 6th Ed (1856):

PRETERITION, civil law. The omission by a testator of some one of his heirs
who is entitled to a legitime, (q.v.) in the succession.
     2. Among the Romans, the preterition of children when made by the
mother were presumed to have been made with design; the preterition of sons
by any other testator was considered as a wrong and avoided the will, except
the will of a soldier in service, which was not subject to so much form.