The Collaborative International Dictionary of English v.0.48:

Liberalism \Lib"er*al*ism\ (-[i^]z'm), n. [Cf. F.
   lib['e]ralisme.]
   Liberal principles; the principles and methods of the
   liberals in politics or religion; specifically, the
   principles of the Liberal party.
   [1913 Webster]

WordNet (r) 3.0 (2006):

liberalism
    n 1: a political orientation that favors social progress by
         reform and by changing laws rather than by revolution
    2: an economic theory advocating free competition and a self-
       regulating market

Moby Thesaurus II by Grady Ward, 1.0:

31 Moby Thesaurus words for "liberalism":
   broad-mindedness, capitalism, catholicity, free competition,
   free enterprise, free thought, free trade, freethinking,
   isolationism, laissez-aller, laissez-faire, laissez-faireism,
   latitudinarianism, left, left wing, leftism, let-alone policy,
   let-alone principle, liberality, liberalness, liberation,
   libertarianism, libertinism, noninterference, nonintervention,
   open-mindedness, progressivism, self-regulating market, tolerance,
   toleration, unbigotedness