The Collaborative International Dictionary of English v.0.48:

Materialize \Ma*te"ri*al*ize\, v. t. [imp. & p. p.
   Materialized; p. pr. & vb. n. Materializing.] [Cf. F.
   mat['e]rialiser.]
   1. To invest with material characteristics; to make
      perceptible to the senses; hence, to present to the mind
      through the medium of material objects.
      [1913 Webster]

            Having with wonderful art and beauty materialized,
            if I may so call it, a scheme of abstracted notions,
            and clothed the most nice, refined conceptions of
            philosophy in sensible images.        --Tatler.
      [1913 Webster]

   2. To regard as matter; to consider or explain by the laws or
      principles which are appropriate to matter.
      [1913 Webster]

   3. To cause to assume a character appropriate to material
      things; to occupy with material interests; as, to
      materialize thought.
      [1913 Webster]

   4. (Spiritualism) To make visable in, or as in, a material
      form; -- said of spirits.
      [1913 Webster]

            A female spirit form temporarily materialized, and
            not distinguishable from a human being. --Epes
                                                  Sargent.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Materialize \Ma*te"ri*al*ize\, v. i.
   1. To appear as a material form; to take substantial shape.
      [Colloq.]
      [1913 Webster]

   2. To come into existence; as, the promised donations never
      materialized.
      [PJC]

WordNet (r) 3.0 (2006):

materialize
    v 1: come into being; become reality; "Her dream really
         materialized" [syn: happen, materialize, materialise]
         [ant: dematerialise, dematerialize]