materialism

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Philosophy The theory that physical matter is the only reality and that everything, including thought, feeling, mind, and will, can be explained in terms of matter and physical phenomena.
• noun The theory or attitude that physical well-being and worldly possessions constitute the greatest good and highest value in life.
• noun Concern for possessions or material wealth and physical comfort, especially to the exclusion of spiritual or intellectual pursuits.

from The Century Dictionary.

• noun The denial of the existence in man of an immaterial substance, which alone is conscious, distinct and separable from the body.
• noun The metaphysical doctrine that matter is the only substance, and that matter and its motions constitute the universe. See idealism, 1.
• noun The doctrine that all phenomena are to be accounted for by the fortuitous concourse of atoms, in connection with certain laws or tendencies toward laws, in nature; Epicureanism.
• noun Any opinion or tendency that is based upon purely material interests; hence, any low view of life; devotion to material things or interests; neglect of spiritual for physical needs and considerations.

from the GNU version of the Collaborative International Dictionary of English.

• noun The doctrine of materialists; materialistic views and tenets; called also philosophical materialism.
• noun The tendency to give undue importance to material interests as contrasted with spiritual concerns; devotion to the material nature and its wants.
• noun R. & Obs. Material substances in the aggregate; matter.
• noun The theory that matter and energy are the only objects existing within the universe, and that mental and spiritual phenomena are explainable as functions of the nervous system of people. Same as materialism{1}.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Constant concern over material possessions and wealth; a great or excessive regard for worldly concerns.
• noun philosophy The philosophical belief that nothing exists beyond what is physical.
• noun obsolete, rare Material substances in the aggregate; matter.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun (philosophy) the philosophical theory that matter is the only reality
• noun a desire for wealth and material possessions with little interest in ethical or spiritual matters