The Collaborative International Dictionary of English v.0.48:

Nativism \Na"tiv*ism\, n.
   1. The disposition to favor the native inhabitants of a
      country, in preference to immigrants from foreign
      countries.
      [1913 Webster]

   2. (Philos.) The doctrine of innate ideas, or that the mind
      possesses forms of thought independent of sensation.
      [1913 Webster]

WordNet (r) 3.0 (2006):

nativism
    n 1: the policy of perpetuating native cultures (in opposition
         to acculturation)
    2: (philosophy) the philosophical theory that some ideas are
       innate