The Collaborative International Dictionary of English v.0.48:

Kidnap \Kid"nap`\ (k[i^]d"n[a^]p`), v. t. [imp. & p. p.
   Kidnaped (k[i^]d"n[a^]pt`) or Kidnapped; p. pr. & vb. n.
   Kidnaping or Kidnapping.] [Kid a child + Prov. E. nap to
   seize, to grasp. Cf. Knab, Knap, Nab.]
   To take (any one) by force or fear, and against one's will,
   with intent to carry to another place. --Abbott.
   [1913 Webster]

         You may reason or expostulate with the parents, but
         never attempt to kidnap their children, and to make
         proselytes of them.                      --Whately.
   [1913 Webster]

   Note: Originally used only of stealing children, but now
         extended in application to any human being,
         involuntarily abducted. Kidnaper

The Collaborative International Dictionary of English v.0.48:

kidnapping \kidnapping\ n.
   the unlawful act of capturing and carrying away a person
   against their will and holding them in false imprisonment.
   [WordNet 1.5]

WordNet (r) 3.0 (2006):

kidnapping
    n 1: (law) the unlawful act of capturing and carrying away a
         person against their will and holding them in false
         imprisonment [syn: kidnapping, snatch]

Moby Thesaurus II by Grady Ward, 1.0:

28 Moby Thesaurus words for "kidnapping":
   abduction, apprehension, arrest, arrestation, capture, catch,
   catching, collaring, coup, crimping, dragnet, forcible seizure,
   grab, grabbing, hold, impressment, nabbing, picking up, power grab,
   prehension, running in, seizure, seizure of power, shanghaiing,
   snatch, snatching, taking in, taking into custody



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

KIDNAPPING. The forcible and unlawful abduction and conveying away of a man,
woman, or child, from his or her home, without his or her will or consent,
and sending such person away, with an intent to deprive him or her of some
right. This is an offence at common law.