To come into existence; become real: Their support on the eastern flank did not materialize. To appear, especially suddenly:"As they plunged down the highway, hazy purple mountains materialized"(Tom Bissell). See Synonyms at appear. To take physical form or shape. Used especially of a spirit or ghost. To cause to become real or actual: By building the house, we materialized a dream. To cause to become materialistic:"Inequality has the natural and necessary effect .. of materializing our upper class, vulgarizing our middle class, and brutalizing our lower class"(Matthew Arnold).