The Collaborative International Dictionary of English v.0.48:

Autonomy \Au*ton"o*my\, n. [Gr. ?: cf. F. autonomie. See
   Autonomous.]
   1. The power or right of self-government; self-government, or
      political independence, of a city or a state.
      [1913 Webster]

   2. (Metaph.) The sovereignty of reason in the sphere of
      morals; or man's power, as possessed of reason, to give
      law to himself. In this, according to Kant, consist the
      true nature and only possible proof of liberty. --Fleming.
      [1913 Webster]

WordNet (r) 3.0 (2006):

autonomy
    n 1: immunity from arbitrary exercise of authority: political
         independence [syn: autonomy, liberty]
    2: personal independence [syn: autonomy, self-direction,
       self-reliance, self-sufficiency]