The Collaborative International Dictionary of English v.0.48:

Humanism \Hu"man*ism\ (h[=u]"man*[i^]z'm), n.
   1. Human nature or disposition; humanity.
      [1913 Webster]

            [She] looked almost like a being who had rejected
            with indifference the attitude of sex for the
            loftier quality of abstract humanism. --T. Hardy.
      [1913 Webster]

   2. The study of the humanities; polite learning.
      [1913 Webster]

   3. A doctrine or ethical point of view that emphasizes the
      dignity and worth of individual people, rejects claims of
      supernatural influences on humans, and stresses the need
      for people to achieve improvement of society and
      self-fulfillment through reason and to develop
      human-oriented ethical values without theism.
      [PJC]

WordNet (r) 3.0 (2006):

humanism
    n 1: the doctrine that people's duty is to promote human welfare
         [syn: humanitarianism, humanism]
    2: the doctrine emphasizing a person's capacity for self-
       realization through reason; rejects religion and the
       supernatural [syn: humanism, secular humanism]
    3: the cultural movement of the Renaissance; based on classical
       studies

Moby Thesaurus II by Grady Ward, 1.0:

34 Moby Thesaurus words for "humanism":
   Christian humanism, Religious Humanism, anthroposophy, bibliolatry,
   bibliomania, bluestockingism, book learning, book madness,
   bookiness, bookishness, booklore, classical scholarship,
   classicism, culture, donnishness, eruditeness, erudition,
   free thought, freethinking, humanistic scholarship,
   integral humanism, intellectualism, intellectuality,
   latitudinarianism, learnedness, letters, literacy,
   naturalistic humanism, new humanism, pedantism, pedantry, reading,
   scholarship, secular humanism