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